The Conservatives have learned their lesson from the economic crash of Black Wednesday when Britain came tumbling out of the ERM, David Cameron has said.
David Cameron: I was there on Black Wednesday
The new Tory leader highlighted how he had been Chancellor Norman Lamont's special adviser when the Tories lost their economic reputation in 1993.
He promised his party would never again risk mortgages and livelihoods.
There needed to be independent checks on the rules set by the government for its management of the economy, he said.
Chancellor Gordon Brown has already made the Bank of England independent and recently announced the Office of National Statistics would follow.
But Mr Cameron said there needed to be an independent panel to judge the Treasury's "golden rule" on borrowing across the economic cycle.
Allowing Mr Brown to decide when the economic cycle began and ended meant the rules lost credibility, he argued.
'I was there'
Mr Cameron outlined the scale of the task faced by his party on the economy.
"Six hundred and ninety Wednesdays ago, my party lost its reputation for economic competence," he said.
"I was there that day, working in the Treasury. You may have seen the TV footage.
"The events leading up to that day were bad for our economy, disastrous for our party, but most important of all made life really difficult for the millions of families who faced high interest rates, negative equity, and repossessions.
"No matter that the policy was backed by the CBI and by Gordon Brown and the Labour Party.
"That was thirteen years ago. We've learned our lesson. I will never let that happen again.
"We will never again take risks with people's mortgages and with people's livelihoods by putting economic stability at risk."
Mr Cameron denied Labour claims that he was planning to create a third fiscal rule of keeping rises in public spending below the overall rate of economic growth.
But he said he wanted to share the proceeds of growth between investment in public services and tax cuts.