The latest official United States documents released by WikiLeaks contain harsh criticism of the British military effort in Afghanistan.
The diplomatic cables, published in Britain's Guardian newspaper, say US and Afghan officials believed that British forces were not up to the task of securing Helmand province on their own.
The US general in charge of NATO forces in 2007, Dan MacNeil, is quoted as saying the British made a mess of things in Helmand.
WikiLeaks also released US diplomatic cables revealing concerns that the Mexican army is failing in its fight against drug cartels.
A cable sent by the American embassy in Mexico City last January described the army as slow and reluctant to take risks. It said troops were not trained to patrol the streets or gather evidence to convict those detained.
Another cable quoted a senior Mexican interior ministry official as saying his government was worried it was losing control of some regions to the drug gangs.
Another leaked diplomatic cable revealed the US accused Sri Lanka's president and a former army commander of mass killings of Tamil people.