Blair traveled to Buckingham Palace where he asked Queen Elizabeth II for permission to dissolve parliament -- a formality that marked the start of the official election campaign.

Upon returning to his Downing Street residence about 20 minutes later, he declared: "There will be a general election in Britain on May 5."

The date -- exactly one month away -- had been widely anticipated for a number of weeks, although it was announced 24 hours later than expected in the aftermath of Saturday's death of Pope John Paul II.

Labor losing lead

Labor is expected to be returned to power, but a fresh crop of opinion polls on Tuesday indicated that it was losing its lead on the main opposition Conservatives, with the Liberal Democrats well back in third place.

"From now until May 5, I and my colleagues will be out every day, in every part of Britain, talking to the British people about our driving mission for a third term," said Blair, who turns 52 on May 6.

He said Labor, in power since May 1997, wanted "to build on the progress made, to accelerate the changes, to widen still further the opportunities available to the British people."

A fundamental choice?

In a swipe at the Conservatives, he said the election would be a choice between consolidating the reforms that Labor has put in place, or a return to a time of uncertainty and instability.

"It's a big choice, a fundamental choice, and there's a lot at stake," Blair said, adding: "Our mission will be driven by values."

One of the opinion polls Tuesday, in the Financial Times newspaper, put the Conservatives five points ahead of Labor at 39 percent. The others showed Labor still in the lead, but only by two to six points.

"Beware yet another election where Mr Blair says one thing to get your vote on polling day and does something quite different afterwards," Tory leader Michael Howard (photo) told a party rally in London. "Mr Blair is already secretly grinning at the prospect of his third victory. Well, you don't have to settle for that."

With polling day now fixed, the House of Commons will have until the end of the week to push through the remaining legislation on its agenda, before the politicians hit the campaign trail in earnest.

Blair as statesman

A Labor victory would clear the way for Blair to play the role of international statesman for the remainder of this year, as he hosts the Group of Eight summit in Gleneagles, Scotland in June. He would also find himself at the helm of Britain's presidency of the European Union in the second half of this year.

Labor, a socialist party before Blair and his finance minister, Gordon Brown (photo), put it on a vote-winning centrist path in the mid-1990s, has never in its history won three elections in a row.

This time round, Labor strategists fear that complacency among bedrock Labor voters, plus anger over Blair's decision to take Britain to war in Iraq two years ago, could see its 161-seat majority in the Commons shrivel.

Last year Blair revealed that if he wins re-election, he intends to serve a full third term -- frustrating Brown's barely concealed ambition to succeed him in the top job.