The Conservatives are set to break their near silence on Europe, Iain Duncan Smith has signalled as he pledged to launch a new debate on the issue.
Duncan Smith made his name as a Maastricht rebel
Divisions with France and Germany over the Iraq war have "changed the terms of the debate" in his favour, says the Tory leader.
Mr Duncan Smith has insisted that his comments don't signal a change in policy - saying he and his frontbench team have been speaking out consistently over the future European constitution and the single currency.
But since winning the party's 2001 leadership battle, Mr Duncan Smith has toned down the Euroscepticism which made him a persistent rebel against the Maastricht Treaty.
In an interview for Friday's Financial Times, he says: "We have the chance to lead the debate in Europe. I'm going to."
You can't put Humpty Dumpty together again
Iain Duncan Smith on European splits
France and Germany's refusal to back a new United Nations resolution on the brink of the Iraq war has fatally undermined the idea of a European super state.
"The problem now is for Tony Blair. You can't put Humpty Dumpty together again ... France and Germany now represent an ideology over Europe which the rest of Europe no longer wants," he continues.
His pledge to speak out about Europe comes as the shape of the European Union is in question.
The convention looking at reforming the EU continues to sit, with the UK Government angry at suggestions of federalism in initial proposals.
The euro debate is also set to come to the fore again, with Chancellor Gordon Brown promising to deliver his verdict by 7 June on whether the UK should adopt the currency.
The Tory Save the Pound campaign before the last general election was seen as one of William Hague's key mistakes as leader.
By giving the issue more prominence again, Mr Duncan Smith risks raising the heckles of pro-Europeans like former Chancellor Ken Clarke.
But most of his frontbench team are noticeably eurosceptic.
In his newspaper interview, Mr Duncan Smith says debate over Europe is "boiling up", although improving public services was still the "big agenda".
"The debate is: can you improve public services, as they stand pretty near unreformed, by spending more money or do you have to do something radically different.
"And I think the public's now ready for an alternative."
With talk of challenges to his leadership currently overshadowed by the Iraq war, Mr Duncan Smith is upbeat about his party's prospects.
He says: "I happen to believe this is the best time to be a Conservative in a generation...
"I don't live by polls... But all the polls tell us that there is a vast number of people who have moved from being benefit of the doubt to undecided...
"Sierra Man, Mondeo Man, whatever it happens to be: there's now a very large proportion of undecideds who could vote Conservative."
Former Tory cabinet minister John Redwood welcomed Mr Duncan Smith's decision to start talking about Europe - an issue on which his party was now "much more united".
Mr Redwood told BBC Radio 4's World At One the Conservatives believed in working with other European countries when it made sense to do so.
But he argued "the EU is now moving on too far in the direction of a centralised state, taking away from us our rights to a democratic government".
Mr Redwood dismissed the idea that voicing such concerns represented a shift to the right-wing, insisting such issues were not about Left or Right.
Most people were sceptical about handing more power to Brussels, he said, and the more the Tories expressed those worries, the more popular they would become.
But Ian Taylor, Tory MP and chairman of the European Movement, told Radio 4's PM programme: "I can't believe that Iain Duncan Smith has any intention of backing the traditionalists in the party who helped us lose heavily at the last general election.
"I simply do not believe that he will wish to make us so marginal that our views on Europe appear to be unelectable because we are not part of the mainstream debate about how we can make more effective our position in Europe rather than just whingeing from the sidelines."
On the same programme, the Tory leader insisted it was not the case that his party had stayed silent on Europe.
He said the Conservatives' main priority was to campaign on public services - but he added that there was an opportunity for the Tories to take advantage of the debate on Europe following rows over Iraq and the ongoing convention on Europe's future.