Tony Blair has vowed to fight for a more integrated Europe despite criticising the French and German governments for rushing into the euro.
In a wide-ranging and hard-hitting speech on the future of the EU, the prime minister batted aside difficulties experienced during the British presidency to present a cautious but upbeat assessment of the future.
"History is on the side of Europe. Despite all the setbacks of recent years, I have no doubt that, in times to come, Europe will be stronger and more integrated," he said.
Blair said that expansion would reinvigorate the EU as it reconsiders its future role in relation to its citizens,
"The fact that we have now been enthusiastically joined by countries like Poland, the Czech Republic and the Baltic states... is inspiring evidence of this forward march of European history," he said.
Despite recent setbacks the prime minister remained positive about the future of the union.
"The irony is that after the shock of enlargement, the crisis of the referendums, the opening of accession negotiations with Turkey and the agreement of the Budget, with a firm process of reform midway through the next financial term - after all these alarms and excursions - there's never been a better time to be optimistic in Europe or enthusiastic about Britain's part in it," he said.
And he dismissed claims that British euroscepticism put the country at odds with its counterparts on the continent.
"The British anxiety is a shared one with the people of Europe; the reform agenda an agreed one with the mainstream of European governments," he said.
"Europe has emerged from its darkened room. It has a new generation of leaders. A new consensus is forming.
"Yes, there is still a debate to be had, but the argument in favour of an open Europe is winning."
And following the six month presidency of the EU - dubbed a fiasco by some critics - Blair said there was a "shining opportunity" to become part of a new consensus about the EU in the 21st century.
But, he added, that meant having to make more realistic assessments about the scale and speed of integration.
"I see a Europe around me that has a long term vision in need of a short term strategy," he said.
"The vision is the one I share with Europe's founders: an ever closer union of nation states, cooperating, as of sovereign right, where it is in their interest to do so."
"I don't support ever closer union for the sake of it; but precisely because, in the world in which we live, it will be the only way of advancing our national interest effectively."
And he saved his harshest words for the French and Germans following the troubled introduction the single currency.
The approach adopted to integration had become "self-perpetuating and certainly self-absorbing".
"A single market benefits from a single currency. But a single currency should come with the completion of the single market," said Blair.
"In truth, however, the political decision to create a single currency was taken first; the economics were treated as if they could be altered by political will. The reality is they can't."
Blair said "a political decision was taken by France and Germany (whilst Britain concentrated on a largely presentational opt-out)" with the result that a timetable was "imposed and the economics made to fit".
And, said Blair, enlargement meant a radical rethink of the "old ways" of the European Union. "Europe won't work if done in the old way. The modern challenges make this so," he said.
"The size of the Union makes it so. The EU doesn't have to create its relevance to its people today; it just needs to discover it."
Despite his criticism, Blair said the EU faced a 'historic opportunity' given the recent changes in powers and composition".
"As for Britain in Europe, globalisation, enlargement and the new security threats Europe faces, not only make the case for engagement not isolation more powerful; but also mean that these changes in Europe, especially enlargement, offer us an historic opportunity to cure the sickness that has afflicted Britain's relationship with the project of European integration ever since it joined the European Community," he said.
Shadow foreign secretary William Hague said the prime minister had failed to say "why prospects for the EU are so bright when he has failed in his two great European projects - the euro and the constitution".
"If a new generation of leaders is now beginning to think seriously about a new, more open Europe it is because the last generation of leaders, Tony Blair among them, have been following the wrong road for Europe," he added.
"Mr Blair can leave office pleased, as we all are, with the achievement of EU enlargement, but his tragedy is that he never developed a strategic British vision for Europe or created a new model for Europe with which the British people could feel at ease."
