Britain’s military operations in Afghanistan have been harshly criticised by the country’s President Hamid Karzai, local officials and the American commander of Nato troops, according to leaked diplomatic papers.

The secret US embassy cables, obtained by whistle-blowing website WikiLeaks, report conversations in which Mr Karzai said that Britain was “not up to the task” of securing the southern province of Helmand and suggested the job would be better given to the US.

US General Dan McNeill, who led Nato forces in Afghanistan in 2007/08, is said to have been “dismayed” by a British effort which “made a mess of things” in Helmand.

And Helmand Governor Gulab Mangal is said to have criticised British troops for failing to get out of their bases and engage with local people.

The 39-year-old Australian is believed to be in hiding in England as the latest publications on his whistle-blowing website fuel global uproar.

The latest revelations, reported in yesterday’s Guardian, sparked indignation among some of those linked to the UK deployment in Helmand, which has swollen to 10,000 troops since it began in 2006. Anthony Philipson, whose son James was one of the first British troops to die in the province, told the BBC: “We have done the best we could with some of the finest infantry in the world, we have taken terrible casualties.

“Yes, the place is still a hotbed of violence, but I think it always will be.”

According to the cables, President Karzai told US officials he was puzzled why security in Helmand had deteriorated after the arrival of British troops.