ITV expects net advertising revenue to be down 20% in September and has revealed a strategy to cut costs by an extra £35m a year by 2010, in its interim results for the first six months of the year.

The commercial broadcaster revealed a year-on-year fall of 28% in pre-tax profits to £91m and a slight 3% increase in revenues to £1.03bn in the first six months of the year.

ITV said its ad revenue forecast for September was below a total UK TV ad market expectation down 17% for the month.

The company said that across the first eight months of the year its ad revenues have come out "flat".

"On current estimates, the television advertising market has weakened in September, where tough year-on-year comparisons apply, given the Rugby World Cup in 2007," the company said. "Whilst ITV has limited visibility on advertising revenues beyond September, ITV expects to outperform the total market over the full year."

ITV said it has "reassessed" the goals of executive chairman Michael Grade's turnaround strategy "in the light of the weaker advertising and economic outlook".

The company has pegged back the target of the global content division, responsible for exploiting programme formats and franchises globally, from £1.2bn by 2012 to £1bn in the same time frame.

It has also extended the time frame for its online revenue target of £150m by 2010 to 2012.

"The change to the previous target… also reflects regulatory delay to the planned Kangaroo service. We expect to meet the revised online target without relying on substantial acquisitions," said the company. "The board remains confident that the turnaround strategy will deliver sustainable, long term growth and is therefore maintaining its investment in programming."

ITV also said today that it has set a new target of achieving £35m in additional cost savings by the end of 2010.

John Cresswell, the chief operating officer and finance director at ITV, said the new cost cutting plan would include job losses and will affect areas including "central services" and the production and broadcasting operations.

The company said it is already "on track" to deliver £41m in savings by the end of 2008 and £40m of additional "regional savings" from the end of 2009.

"We cannot control the economic environment in which we operate," said the ITV executive chairman, Michael Grade. "As a result of the recent slowdown in the television advertising market, the board has taken some tough decisions which are reported here today."

Grade said that "in the light of the uncertain economic outlook and the importance of maintaining programming investment" the company has reduced the interim dividend to 0.675p per share.

ITV said that as a result of reduced advertising market forecasts for 2008/9 it was taking a non-cash impairment charge of £1.6bn included in operating costs in its income statement.

ITV's share of commercial impacts – the viewing of one ad, one time by one person – was flat at 41.4% year-on-year in the first six months, although flagship ITV1 has seen its share fall by 5.1% for the period.

Online revenues, from web operations including ITV.com and Friends Reunited, were up 6% year-on-year in the first six months.

ITV1 network programme budget will be held at its 2007 level.

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