The governor of the Bank of England has indicated that an onslaught on his performance by the Conservative party establishment will not influence whether he stays in his post beyond 2018.

Asked by a House of Lords committee whether high-level interference will force him to leave, Mark Carney said he would not be swayed by political issues as he weighs up the option of departing in two years’ time or extending his contract by a further three years to 2021.

“It is entirely personal, and no one should read anything into that decision in terms of government policy, actual, imagined, potential, past, etc. This is a role that requires total attention, devotion, and I intend to give it for as long as I can. But those are the only factors,” he said.

A section of Theresa May’s Tory conference speech on the impact of the Bank’s monetary policy was viewed as a veiled attack on Carney’s strategy - although No 10 has sought to reassure Threadneedle Street that the comments were not intended as a personal attack. Carney has also been criticised by Conservative figures including Michael Gove and William Hague, in newspaper articles that questioned his leadership. Other Tory figures, including the former chancellor Nigel Lawson, have criticised the Bank’s pre-Brexit referendum warnings that a vote to leave the EU would damage the UK economy.

Carney, a Canadian, initially agreed a five-year term with the then chancellor, George Osborne, and is due to say before the end of the year whether he will take up an option to stay until 2021.

His comments at a House of Lords economic affairs committee hearing came after he was questioned about the prime minister’s conference speech this month, when she criticised the “bad side-effects” of the Bank’s monetary policy approach of low interest rates and a quantitative easing (QE) money-printing programme.

Her criticism was followed by comments from the former foreign secretary William Hague, who attacked the Bank’s low interest rates and the £435bn QE package – where the Bank buys bonds from financial institutions – for crushing returns to pension funds and ordinary savers.

The former minister Michael Gove, who likened Carney to an “inviolable” Chinese emperor, said the governor regarded criticism as a thought crime “and those who dare to question his rule are flayed in the press with dire warnings left hanging in the air to emphasise the governor will brook no challenge to his authority”.

Speaking to the House of Lords committee, Carney said that taking the Bank under political control would have an immediate cost to the government in the form of higher borrowing costs. He said it would spook investors, who were likely to demand a higher return for holding British assets, including government bonds used to fund state spending.

He said it was up to the Bank’s policymakers to achieve stable prices without interference, though based on a remit set by parliament.

“That process has stood the test of time. That process is the process that the BoE is following and if it were to be called into question, one would expect to see the emergence of a risk premium around a range of UK assets, it would be most prominent around the currency, in gilt markets, in inflation expectations,” he said.

Carney said he did not think the passage in May’s speech calling for “a time for change” referred to the Bank’s independence and was not proposing a change in the way monetary policy is set.

The chancellor, Philip Hammond, backed Carney last week, saying the Bank’s independence was an essential element of Britain’s financial system.

But one of Hammond’s Conservative predecessors, Lord Lamont, said Threadneedle Street’s arms-length status was hampered by the Bank’s need for permission from the Treasury for every bout of bond-buying under QE. “Surely the Bank’s independence is compromised when the Treasury can sanction each tranche of bond buying,” he said.

Earlier, in the Commons, Hammond responded to questions about the Bank’s independence, saying that the Bank’s bond-buying scheme has been highly effective so far, and hinted that he would not obstruct another dose if needed.

“No request for quantitative easing has ever been refused, and I can’t see why it would be different in future,” he said.

The pound had fallen below $1.21 ahead of Carney’s appearance, but subsequently recovered to around $1.22 by early evening on Tuesday.