An eccentric ex-journalist from the opposition Conservatives ousted the Labour mayor of London Saturday, capping an election rout for British Prime Minister Gordon Brown who faces an uphill battle to revive his government's fortunes.

Gaffe-prone lawmaker Boris Johnson beat maverick left-winger Ken Livingstone in the capital, the key prize in council elections on May 1 that the British media said became a "May Day Massacre" for Labour.

They were Labour's worst local election results in four decades, and a blow to Brown in his first test at the ballot box since he took over from Tony Blair in June.

Brown is expected to launch a fight back as early as next week, when a new legislative programme is outlined.

He admitted the loss of more than 300 council seats across England and Wales was "bad", but blamed the effects of the global credit crunch for the centre-left party's defeat.

"We have lessons to learn from that and then we will move forward," he said.

The loss of the London epitomized the scale of the defeat for the government, which has been fighting criticism of its economic record, botched tax reforms and public anger at rising fuel, food and energy costs.

Johnson, with his shock of blond hair and flowery language, was considered a joke candidate at the start of the campaign, but he secured a clear victory over Livingstone.

Six months ago the man dubbed "Red Ken" for his once fiery left-leaning views, seemed set for a third term.

Johnson, 43, worked for the Daily Telegraph newspaper and edited right-wing magazine The Spectator but came to wider public attention when presenting a satirical television game show and sometimes displayed a tendency to put his foot in his mouth.

But his campaign -- "A Change For The Better" -- surprised many, focusing heavily on claims of cronyism surrounding Livingstone, promising to tackle crime on London's streets and seizing on disaffection with the government.

He will now be London's public face in the run-up to the 2012 Olympic Games and one of the Conservatives' key figures going into the next general election, which must be held by mid-2010.

Emerging from his north London home Saturday, Johnson was all business, saying he had been elected "on a very clear manifesto to clear up crime" and was heading to meetings on police and transport.

In his acceptance speech, he said he hoped his victory signalled improving fortunes for the Conservatives, who have been out of government for exactly 11 years to the day of the mayoral vote.

"I do not for one minute believe that this election shows that London has been transformed overnight into a Conservative city," he said.

"But I do hope it does show that the Conservatives have changed into a party that can again be trusted."

Senior government figures backed Brown, but Home Secretary Jacqui Smith, the interior minister, admitted voters had given Labour a "kick in the backside."

Former foreign minister Jack Straw said the party had alienated its traditional working-class voters by scrapping the lowest, 10-pence (13 euro cents, 20 US cents) tax band.

"The 10p thing was the key thing in the elections," Straw said, but he insisted Labour could recover to win a fourth consecutive term in government.

"I am very clear that the situation in two years' time will be different from where we are today," he told BBC radio.

Left-wingers warned however that Brown was running out of time to prove he could make a successful transition from a widely admired finance minister to prime minister.

Backbencher Ian Gibson said: "I'll give him six months to do it or there will be really hard talking."

Newspapers said Brown faced a struggle to stave off what many saw as a Tory renaissance.

The Independent said Labour had suffered a "May Day Massacre", while the Daily Telegraph said it was "Meltdown for Brown."

Editorials said while a Conservative government was now a possibility, leader David Cameron must concentrate on vaguely sketched-out policies to become a credible "government-in-waiting."

In the local polls, the Conservatives took 44 percent of the national vote -- enough to secure a sizeable parliamentary majority if the results were repeated at a general election.

The Liberal Democrats took 25 percent and Labour 24 percent.

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.Brown faces an uphill battle to revive his government's fortunes

AFP