Brown warns Karzai he could lose backing

By Adrian Croft

LONDON (Reuters) - Afghan President Hamid Karzai, winner of a fraud-tainted election, risks losing British and international support unless he acts decisively to fight corruption, Prime Minister Gordon Brown said on Friday.

Brown, seeking to bolster dwindling public backing at home for keeping British troops in Afghanistan, said Karzai must pass five key tests.

He listed them as fighting corruption, building up Afghan security forces, promoting reconciliation, encouraging economic development and fostering closer cooperation with Pakistan.

"If the government fails to meet these five tests, it will have not only failed its own people, it will have forfeited its right to international support," Brown said in a speech at the Royal College of Defence Studies in London.

NATO's Afghan mission involves 65,000 U.S. troops and 39,000 from allied nations, including 9,000 from Britain.

Karzai's controversial re-election and rising losses among its force in Afghanistan have led many in Britain to ask why the British troops are there.

A new YouGov poll for Channel 4 news found that 57 percent of people thought it was impossible for British troops to win the war against Taliban insurgents and 73 percent wanted British troops home within a year -- up sharply from last month.

"I am not prepared to put the lives of British men and women in harm's way for a government that does not stand up against corruption," Brown said in his toughest public message to Karzai.