American military chiefs are to send up to 9,000 troops to Helmand next year, potentially sidelining the UK’s 5,000-strong force in the southern Afghanistan province. The first of three US brigade combat teams is expected to be operational by the spring. Their main base is under construction alongside the British headquarters at Camp Bastion.

The move comes amid US frustration that the British have insufficient soldiers and helicopters to maintain security and reconstruct Helmand, with the Taliban acting freely in large tracts of the province.

President George W Bush is expected to announce a surge of US troops into southern Afghanistan after next month’s White House election.

General David McKiernan, the US commander of all allied forces in Afghanistan, has asked for at least four brigade combat teams for Afghanistan, but most will go into Helmand.

British sources said the revelation that the bulk of the troops were to be sent to Helmand made it doubtful the British could stay in charge.

There are also likely to be differences over tactics. US commanders are more inclined than the British to call in close air support, which heightens the risk of civilian deaths.

British commanders have repeatedly said they need more troops if they are to impose security in Helmand, but the government has refused to provide them. “The Americans are really applying the pressure, but the fact is we cannot defeat the enemy with the resources we have,” one senior British officer said.

There are echoes of the irritation felt by US officials over last year’s UK withdrawal from Basra in Iraq, he said.

The failure of the British effort in Helmand was highlighted two weeks ago when Taliban fighters marched on the provincial capital of Lashkar Gah and attacked the governor’s house just yards from the UK base.

A Pentagon spokesman said: “It is not our intention to displace British troops. It would be an effort to complement their efforts.”

He confirmed 800 troops would deploy shortly and a brigade combat team of 3,000 would deploy in the spring.

Deal on American presence in Iraq close to collapse, page 26

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