The Guardian newspaper reported that the US and its European allies are preparing to plant a high-profile figure in the Kabul government in a direct challenge to Karzai.

The daily said no names had emerged for the new role but the US held in high regard the reformist interior minister Mohammed Hanif Atmar who was appointed in October.

The creation of a new chief executive or prime ministerial role is aimed at bypassing Karzai, the report said, adding that in a further dilution of his powers, it is proposed that money be diverted from the Kabul government to the provinces.

"Many US and European officials have become disillusioned with the extent of the corruption and incompetence in the Karzai government, but most now believe there are no credible alternatives, and predict the Afghan president will win re-election in August," the report said.

In a report from Brussels and Washington, the paper said a revised role for Karzai had emerged from the White House review of Afghanistan and Pakistan ordered by Barack Obama when he became President.

The review is likely to be unveiled at a special conference on Afghanistan at The Hague on March 31, the report said.

"...By installing a senior official at the president's side capable of playing a more efficient executive role, the US and Europeans are seeking to channel resources to the provinces rather than to central government in Kabul," the Guardian reported.

It quoted a diplomat with knowledge of the review as saying: "Karzai is not delivering. If we are going to support his government, it has to be run properly to ensure the levels of corruption decrease, not increase. The levels of corruption are frightening."

According to the report, the idea of a more dependable figure working alongside Karzai is one of the proposals to emerge from the White House review, completed last week.