PM warns Karzai on Afghan corruption.

GORDON Brown warned Afghanistan's re-elected president yesterday that he will "forfeit the right to international support" if he fails to root out corruption.

The Prime Minister also told President Hamid Karzai a home-grown army must be built to take over responsibility for security in his country.

Mr Brown made clear that he was not threatening to pull Britain's 9,000-strong military force out of Afghanistan, insisting: "We cannot, must not and will not walk away."

But it is thought Mr Karzai faces the threat of withdrawal of international backing for him personally and for his administration if he fails to deliver on five key tests set out by Mr Brown, relating to governance, security, reconciliation, economic development and relations with neighbouring Pakistan.

Defending Britain's mission in Afghanistan, Mr Brown warned that al Qaida was still training and plotting attacks from the region and UK troops were "our first line of defence" against terror attacks at home.

And in a message to allies in the 43-nation Isaf coalition not to waver in their commitment, he said: "We must persist together. In our different ways we must all contribute. In the end, we will succeed or fail together - and we will succeed."

The Prime Minister's warning came in a speech to military top brass in London at the end of a bloody week for British troops, with seven dead including five murdered by a "rogue" Afghan policeman.