A re-elected Labour government would not recommend joining the euro unless the economic case for British membership was "clear and unambiguous", Gordon Brown told the BCC conference.
He stressed that the Treasury?s five economic tests must be met before the issue of joining was put to a referendum.
?While we support the euro in principle, we have been determined that, to ensure stability, any decision must be based on the national economic interest and be clear and unambiguous,? he said.
?And I believe that we were right to conclude in this Parliament, when we examined the five tests in detail, that we could not recommend joining.
?In the next Parliament, and at all times, I can guarantee that the five tests would have to be met and the results clear and unambiguous. Stability and the national economic interest will always come first.?
On pensions, Mr Brown said he was confident that a cross- party consensus would emerge on how to tackle the massive shortfall in retirement income faced by millions of people.
In response to questions from the floor, the Chancellor said a national debate on pensions would be a key element of a third term Labour administration but any radical legislation would have to await a new Parliament.
?I do believe we can get all-party consensus and a consensus that lasts beyond one government,? he said.
?There is no rush to legislation and if it?s radical then will have to wait for a future Parliament.?
Mr Brown commissioned former CBI leader Adair Turner to report on pensions and advise on how to plug the savings gap, which some experts say could be about #60 billion.
In an interim report last autumn, Mr Turner said there would be a ?major problem? unless taxes rose, individuals saved more or the retirement age raised.
Meanwhile yesterday, Conservative Party leader Michael Howard said Britain should look to the US and not red tape-burdened Europe as the model for its economy.
He pledged that Britain would ?change direction? under a Conservative Government as he sought to woo the votes of the UK?s business leaders.
Europe ?should be a market for British business not an economic model?.
Speaking as his party unveiled its business manifesto, with pledges to slash bureaucracy and waste, he also repeated his pledge to keep Britain out of the single currency.
?I don?t want British business to be burdened with all the regulation and red tape that weighs down on business in continental Europe,? he said.
?When you hear Gordon Brown going on about the need to make the European economy more like America?s, you might think he agreed with me.
?The great irony is that he?s actually making Britain?s economy more and more like those of continental Europe.
?Europe should be a market for British business, not an economic model.? Mr Howard said that the Tories would give business a government that was ?on its side, not in its way?.
? A government that spends within its means; a government that doesn?t take risks by over-spending and over-borrowing; a government that won?t hand over control of our interest rates to the European Central Bank.