After a rough day’s trading, Britain’s FTSE 250 index has lost almost 2% of its value today.

The FTSE 250, which contains UK-focused firms, shed 351 points to 17492. Holiday firm Thomas Cook shed almost 14%, housebuilder Crest Nicholson shed 8.5%, transpor group Stagecoach lost 8.3%, and Domino’s Pizza lost 8%.

The FTSE 100, packed with internationally-focused companies, shed 53 points or 0.8% - close to last-week’s two-week low.

Fiona Cincotta, senior market analyst at City Index, says shares were hit by Theresa May’s humiliating u-turn today.

The vote was meant to be taking place after five days of intense debate in Parliament over Theresa May’s proposed Brexit deal but instead the change of plans ended up with MPs baying for blood including Jeremy Corbyn asking for the PM to “give way.”

There is no clear indication about where the MPs or the Prime Minister plans to take things next.

UK business groups are united in horror at events in parliament today:

Rather than a crunch vote on Tuesday, the markets now face days of uncertainty, or quite possibly several weeks.

Theresa May is refusing to say when the delayed Meaningful Vote will take place, only that it will be held once she has secured new reassurances on the backstop.

The cost of insuring UK government debt against default has jumped to its highest level since the EU referendum, in another sign that investors are getting jittery.

The pound remains on track for one of its worst days since the 2016 referendum.

It’s recovering, slightly, from its lowest point today -- but still down 1.6 cents at $1.256.

Lukman Otunuga, research analyst at FXTM, says the possibility that the prime minister is ousted from Downing Street is pulling sterling lower.

It is not just the likelihood of a no-deal Brexit that investors are factoring into their valuations of the British Pound.

Investors are also re-pricing into the market the increased likelihood that Theresa May will once again be at threat to expectations of a leadership challenge. Another emerging danger is that the decision taken today raises the threat level that the UK is falling into a disorderly Brexit trap.

Lee McDarby, Corporate IP Managing Director at foreign exchange firm moneycorp, says Theresa May’s decision to delay the Brexit vote will hurt the economy:

“Over the course of the afternoon we’ve seen wild swings in the value of Sterling, including a 20 month low against the dollar.

Every time the Prime Minister kicks the can down the road, the uncertainty dents British business plans for 2019. Right now it seems the markets are just looking for some certainty on the future of the UK, regardless of its shape or form.”

The pound has fallen further against the euro too. Now down 1.4%, or one and a half eurocents, at €1.1014.

That means the euro is worth 90.7p, its strongest position since late August. This makes imports from Europe more expensive, and UK exports more competitive.

So much for Theresa May’s speech being priced in! This chart shows how sterling has taken a deeper bath, as MP after MP criticise the PM’s handling of the Brexit negotiations.

The PM’s position in a nutshell:

Theresa May is now challenging MPs to support her deal, calling for compromise.

She says MPs must admit that a second referendum risks dividing the UK again, that single market membership means maintaining free movement of people, and no deal would cause economic damage.

But, the House of Commons sounds as divided as ever....

Theresa May is giving her statement to the House of Commons now.

Our Politics Live blog will have full coverage. I’ll track financial reaction to the key points.

Theresa May has been working the phones....but not finding many friends at the other end of the line.

The Sun’s political editor, Tom Newton Dunn, has tweeted that MPs might not get to vote on Theresa May’s Brexit deal until 2019.

If so, that wouldn’t calm the financial jitters dragging down the pound.

More pressure on the PM, from the head of the DUP - who have been propping her government up since the 2017 election.

Andy Scott, Associate Director at financial risk management consultancy JCRA, fears the pound will suffer further losses as the Brexit drama plays out:

Theresa May is reported to be planning to travel to Brussels to seek a legally-binding assurance on the back stop, in an attempt to gain support of MPs who fear being trapped indefinitely under the current proposal.

But with her authority severely depleted, the political stakes are high for May whose position as Prime Minister could soon be deemed untenable.

“The uncertainty will meanwhile continue to exert downwards pressure on Sterling.”

The slump in the pound today shows that international investors are losing faith in Theresa May’s government, says the BBC’s Simon Jack:

MPs are due to hear from Theresa May in less than 30 minutes time, in what’s certain to be a testing appearance at the dispatch box.

Paul Hardy, Brexit director at legal firm DLA Piper, argues that the pain may not be worth it:

“The political cost to Theresa May of delaying the vote could only be justified if she can come back from Brussels with significant changes to the draft Withdrawal Treaty - this is the legally binding document which puts the Irish backstop in place.

This seems unlikely if the comments of the European Commission President, Jean-Claude Junker, made at the time the deal was adopted are taken at face value: “This is the best deal possible. I’m inviting those who have to ratify this deal in the House of Commons to take this into consideration. This is the best deal for the UK, the best deal for Europe, this is the only deal possible”.”

At today’s 18-month low of $1.261, the pound in your pocket is worth 15% less than on the day of the EU referendum.

However, it’s still stronger than in the aftermath of the vote; sterling hit a 31-year low below $1.20 in January 2017, before managing a small recovery.

And in historical terms, it’s just one more devaluation in a series of sterling crises.... including Black Wednesday in 1992, the Wilson devaluation in 1967, the 30% devaluation by the Attlee government, the end of the gold standard....

We also have fresh evidence that all the Brexit uncertainty is weighing on the economy.

The National Institute of Economic and Social Research has estimated that UK growth will slow to 0.4% in the current quarter, down from 0.6% in July-September.

That follows official data this morning, showing that UK manufacturing shrank in October, and that the wider economy only grew by 0.1% last month.

Sterling’s weakness isn’t helped by confusion over whether Theresa May can actually scrap tomorrow’s vote or not!

However, the government may use parliamentary procedure to avoid the humiliation of losing a vote on whether to cancel its own vote.

My colleague Jessica Elgot explains:

A government source has said that there won’t be a vote on a business motion to cancel Tuesday’s vote. (See 1.38pm.) “We are replacing the business with a new statement but it isn’t a motion and therefore isn’t voteable,” the source said.

Reminder: Our Politics Live blog has all the latest from Westminster (I’m tracking the financial reaction here...)

A further burst of selling pressure is threatening to send sterling below $1.26, for the first time since June 2017.

As you can see, the pound has suffered a series of sickening jolts in the last few hours, since news broke that Theresa May was holding an emergency call with the cabinet.

The latest chatter in Westminster is that May plans to return to Brussels, in search of a better deal (given the torrent of criticism over the Irish backstop).

.... meanwhile, the leader of the Scottish Nationalist Party, Nicola Sturgeon, has publicly called for a vote of no confidence in the government.

The pound is continuing to lose ground, as traders prepare to hear from Theresa May this afternoon.

Sterling is now down a whole eurocent against the euro at €1.1078, the lowest since September. That means the euro is worth more than 90p.

Against the US dollar, sterling has just scraped a new 18-month low, down almost one cent at $1.263.

Jaws have been dropping across the City in the last few hours. Banks, stock brokers and foreign exchange firms had all drawn up plans for a big night on Tuesday, as the Meaningful Vote took place.

Hotels were booked, caterers arranged, as traders prepared for a big all-nighter.

Now, investors are watching Westminster to see how the saga develops.

Here’s how Brad Bechtel of investment bank Jefferies summed up the situation to clients:

The risk of a disastrous vote scenario was too high and therefore they felt it prudent to delay for now. Don’t honestly know if that is a good or bad thing.

Either the vote was going to be so bad that postponing it is a good thing, or the postponement of the vote tells you how far away from a good scenario they are.

Conservative MP John Redwood is speaking on Bloomberg TV now.

Redwood - a long-standing Brexiteer - argues that the UK should leave the EU without a deal, thus saving the £39bn divorce payment:

We won’t be crashing out, we’ll be cashing in.

Redwood says that a ‘clean’ Brexit would be a great opportunity to strike new trade deals....

...but US investors aren’t convinced by the MP for Wokingham.

Marc Chandler, chief market strategist at investment group Bannockburn Capital, is also on the show. He says that delaying tomorrow’s Brexit vote means more uncertainty (bad for markets).

People think that leaving without a deal would be bad for sterling.

The financial markets have been plunged into fresh upheaval today, says Simon Harvey, FX Analyst at Monex Europe:

“When the market thought uncertainty had finally peaked, May’s delay proves it wrong”

The chaos in Westminster is hurting the stock market too.

Shares in house builders, who are vulnerable to an economic slowdown, are falling. Barratt Development are down 3%, Taylor Wimpey has lost 2%, and Crest Nicholson down 7%.

Other UK-focused companies are suffering too, such as Primark-owner ABF (down 2%), ITV (down 3.5%) and the AA (down 5.5%).

Britain’s FTSE 250 index, which contains UK-focused companies, has fallen by 1% today.

The blue-chip FTSE 100, though, is up 7 points, thanks to the weakening pound (which boosts the overseas earnings of multinational companies).

No prizes for spotting the moment when traders heard that the Brexit vote might be off....

This chart shows how the pound has now dropped to its lowest level against the US dollar since June 2017

City traders are scrambling to keep up with events in Westminster. The latest news is that Theresa May will address parliament this afternoon....

Investors had been preparing for major volatility on Tuesday night, when the Meaningful Vote took place. Instead, the drama is coming a day early.

Hamish Muress, currency analyst at OFX, said:

The confusion over whether tomorrow’s Brexit vote will go ahead provides the market an insight into the chaos and disagreement within Downing Street. Rumours that Theresa May is set to pull tomorrow’s vote contradict those of a Downing Street spokesperson, and the fact the news was broken over a conference call instead of in a cabinet meeting speaks volumes.

“Many predicted that tomorrow would be the big day for any movement in the pound. However, it has already reached three-month lows against the euro and, depending on whether the vote tomorrow goes ahead, could hit lows last seen against the dollar in August.”

S.M. Lodha, chairman of UK insulation firm Western Thermal Group, fears that the UK economy will continue to struggle until Brexit is resolved:

It is evident that this economic slowdown has been impacted by the extremely low business confidence levels amongst businesses and entrepreneurs in the UK with the ongoing Brexit negotiations leaving businesses in a state of hesitancy and reluctance to invest in opportunities or growth.

As long as the UK’s future continues to be uncertain, the more business growth will be stagnated.”

Another reason to worry....

Marina Mensah-Afoakwah, senior economist at the CEBR think tank, also blame Brexit for the UK’s slowing economy:

“Today’s data show that the UK economy has continued its slowdown into Autumn, as business and consumer confidence take a hit amidst Brexit uncertainty.

She also points out that the service sector provided most of the growth in the last few months, while manufacturing contracted last month:

October’s GDP growth was mainly driven by services. Rolling three-month growth in the sector was 0.3% in October, which contributed 0.23 percentage points to overall GDP growth. This was largely as a result of growth in IT and professional services, which grew by 1.7% and 1.3% respectively. Construction also contributed positive growth, up 1.2% in October.

However, the manufacturing sector saw no growth at all in the three months to October, mainly due to a decline in the pharmaceutical industry. While in the three months to October growth in the manufacturing industry was flat, monthly figures for October show that sector actually contracted by 0.9%.

Economist Rupert Seggins has analysed today’s growth figures, and pulled out some key points:

Although monthly GDP figures are volatile, it’s clear that the UK economy has slowed since the summer:

This chart shows how the UK’s growth rate has petered out, as the bumper consumer spending boost in July drops out of the data.

[Each data point compares a three-month growth period to the previous quarter]

Rob Kent-Smith, head of national accounts at the ONS, says the UK economy has weakened this autumn:

“GDP growth slowed going into the autumn after a strong summer, with a softening in services sector growth mainly due to a fall in car sales. This was offset by a strong showing from IT and accountancy.

“Manufacturing saw no growth at all in the latest three months, mainly due to a decline in the often-erratic pharmaceutical industry.

Construction, while slowing slightly, continued its recent solid performance with growth in housebuilding and infrastructure.”

Britain’s economy has now barely grown over the last three months.

Today’s growth report shows that GDP was flat in August and September, before inching up by 0.1% in October

Over in Japan, prosecutors in Japan have charged Carlos Ghosn with under-reporting his income -- three weeks after the former Nissan chairman was dramatically arrested.

And in another twist, prosecutors also indicted Nissan for filing false financial statements. That could leave other senior executives facing tough question, such as CEO Hiroto Saikawa, who was scathing about Ghosn’s performance after his arrest.

Brexit anxiety is also bubbling in the markets today, as investors prepare for MPs to (probably) reject Theresa May’s deal tomorrow.

The government is on track for a stonking defeat (assuming the vote goes ahead), meaning there’s plenty of chatter about leadership bids, no-confidence votes, and general elections.

Shares in UK-focused companies such as house builders and retailers are among the top fallers in London this morning. And sterling is bobbing around $1.27, a whole five cents lower than in late September.

Neil Wilson of Markets.com says

Given the way political risk is starting to be priced into the market, we could see further losses if, or rather when, the prime minister loses her Brexit vote.

Whilst a weaker pound could offer some support, a very high political risk premium would tend to trump that and drag the market lower. Investors will have to start, if they haven’t already, price in the risk of a General Election and Labour-led government.

In another twist, Europe’s top court has ruled that the UK can unilaterally stop the Brexit process, and remain in the EU on the same terms....

O.M.G

Shares in UK outsourcing firm Interserve have cratered by three-quarters this morning, to just 6p, as the government contractor battles to negotiate its second rescue deal this year.

The heavily indebted group, which has thousands of government contracts such as cleaning hospitals and serving school meals, said the rescue plan would mean substantial losses for current shareholders as the banks that have lent Interserve more than £600m take control of the company. It hopes to wrap up a deal early next year.

Interserve’s shares plunged to 6p in early trading, giving it a market value of less than £9m. At its peak in 2014, the shares were worth more than 700p.

Today’s losses have dragged the Australian stock market to a two-year low (a milestone which Britain’s FTSE 100 struck last week).

Stock markets have also been hit by the news that Japan has suffered its worst contraction in four years.

Revised GDP figures show that the Japanese economy shrank by 0.6% in July-September, or 2.5% on an annualised basis, worse than first estimated.

Growth shrank as companies slashed spending, as the US-China trade war hurt demand for exports.

Japan was also hit by several natural disasters during the quarter, including Typhoon Jebi (the worst in 25 years) and a destructive earthquake in Hokkaido. This forced factories to cut production.

Artjom Hatsaturjants of Accendo Markets says Japan’s contraction is “adding further fuel to the fire that set the stock markets red”.