Shadow chancellor George Osborne acknowledged today that a Conservative government might find it difficult to cut taxes if it wins power at the next general election.
Mr Osborne, who addresses the party's Spring Forum today in Gateshead, said they may inherit a "huge borrowing problem" after Chancellor Alistair Darling warned in his Budget that public finances were set to plunge further into the red.
While he said the party had a long-term commitment to try to cut taxes, he said he would not do anything to jeopardise economic stability.
"I cannot make a promise at the election that there will be a big reduction in the burden or there will be big tax cuts because I may well inherit a situation, if people vote Conservative in the general election, where I have huge borrowing figures to deal with," he told BBC Radio 4's Today programme.
"Already government borrowing next year is £7 billion higher than Alistair Darling was predicting just a couple of months ago so we might have a huge borrowing problem.
"It is my ambition to reduce taxes on families and reduce taxes on businesses, but of course the stability of the economy and the soundness of the public finances must come first."
His comments will frustrate those on the Tory right who have been pressing the leadership to make tax cuts a priority, believing that a big reduction could kickstart the economy.