Hillary Clinton apologised yesterday for the derogatory comments made by American diplomats about British political leaders and military forces in the leaked cables published by the WikiLeaks website.
The US Secretary of State has made a frantic round of calls to foreign governments over the last week to try to limit the international fall-out from the disclosures.
They have revealed American disdain for Britain's handling of the turbulent Helmand province in Afghanistan and passed on unflattering assessments of David Cameron and George Osborne.
"I personally want to convey to the government and the people of the United Kingdom both my deep respect and admiration for the extraordinary efforts and our regret if anything that was said by anyone suggested the contrary," she said.
While expressing her regret, she maintained that politicians, officials or advisers have to be able to speak to each other frankly and in confidence in order to govern effectively.
In Kabul, the leak of cables critical of the Afghan government and of President Hamid Karzai, who was described as weak and unfamiliar with nation-building, are a source of great anger and concern.
US diplomats fear the leaks may have caused irreparable damage to the Karzai regime, and have spent several days in a rearguard action trying to assure the Afghan government of its support and confidence.
Julian Assange, the WikiLeaks founder, answered online questions yesterday and declared Bradley Manning, the US soldier suspected of leaking 250,000 documents to him, as a hero. Mr Assange refused to divulge whether Mr Manning, who has been charged by the US Army with mishandling and leaking classified data, was the source but said: "If indeed ... Bradley Manning is behind some of our recent disclosures, then he is without doubt an unparalleled hero."