The Tories are set to call for a vote of no confidence in Chancellor Gordon Brown after his decision to scrap tax relief on pension funds in 1997, despite claims he received pension advice to the contrary.

George Osborne, the shadow chancellor, has claimed that his party’s Commons motion will be a test of whether Brown has “the political courage to apologise”.

The Treasury confirmed that Brown will be responding to the Tories’ challenge, although political observers are confident that Labour’s big majority will see the chancellor through unscathed and with his reputation possibly enhanced.

The recent release of Treasury documents under the Freedom of Information Act had led to claims that Brown had ignored the expert pension advice of his officials when he abolished tax relief on pension funds.

Osborne said: “This is Gordon Brown’s chance to explain why he sought to hide the dangers of his reckless raid on pensioners’ savings. After the revelations about the raid, how can anyone have confidence in his judgement?”

He continued: “We shall see if the chancellor has the political courage to apologise to millions of pensioners affected.”

But Ed Balls, economic secretary to the Treasury, defended the decision the relief for pension funds as part of the package of business tax reforms designed to improve economic competitiveness.