The friendly-fire deaths in Helmand have reopened a schism between American and British troops over how to fight the Taleban in Afghanistan.

Although publicly British commanders insist the Americans are still a vital ally in the fight against insurgents, privately British soldiers expressed concern and anger at their "gung-ho" approach.

Squadron Leader John Gunther, a British spokesman in Helmand, told The Times: “The Americans have helped us out on many occasions. The cause of the accident is under investigation, what I will say is that although tragic, friendly fire incidents are rare and are part of armed conflict.

“We have methods in place to stop this, but they are not fail-safe.”

However, news that an investigation was being launched did little to appease the British soldiers on the ground.

“I just can’t figure out how this has happened. How do you tell the families they were killed by supposed allies?” one British soldier asked.

“Whenever I hear we have American jets overhead I get f***ing worried,” another serviceman said. “They just don’t seem to know what they are doing a lot of the time.”

“They have a different approach to us, they fire first and think later,” said another.

“Here we are fighting the Taleban and they (US warplanes) are dropping bombs on us," said a British soldier. "They are meant to have the best equipment, yet this still happens time and time again. You have to wonder what they are doing.”

Earlier this month an unnamed senior British officer told The New York Times that differences in tactics were such that he had asked American Special Forces teams to pull out of the town of Sangin, in Helmand, because they were causing so many casualties and undermining support for reconstruction projects.

The US forces also planned to build a patrol base near a religious shrine and a graveyard — a proposal only abandoned after British troops intervened.

Des Browne, the Defence Secretary, was forced to issue a statement after the report, in which he said the views were those of a single officer. "It is not the view of the alliance. These things can be said in the heat of battle," he said.

But when The Times visited Sangin last month, other soldiers were willing to describe the difficulties of working with their allies. “They just seem to have no idea how to fight a counterinsurgency, we have a history but they have no reference points” said one soldier.

“They have a different approach to us, if we get in an ambush we pull back and assess the situation," said another. "They try and shoot their way through it and kill as many people as possible.”

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