The whistle-blower website WikiLeaks is to release almost 3 million documents on the internet, including thousands of sensitive diplomatic cables sent to Washington from the American embassy in London, The Sunday Times reported.
It said the British government has warned that its citizens in Pakistan, Iraq, Iran and other parts of the Muslim world could be targeted in a violent backlash over "anti-Islamic" views expressed in diplomatic documents. Some disclosures may put pressure on Britain's "special relationship" with the US by revealing the private views of diplomats on former premier Gordon Brown, the present Prime Minister David Cameron and his deputy Nick Clegg.
Brown's rocky relationship with US President Barack Obama that included a visit to New York in September 2009 during which the White House was accused of "snubbing" the former prime minister, is almost certain to be mentioned as is Britain's troop withdrawal from Iraq, The Sunday Telegraph said.
But officials said the real damage could be done by the disclosure of cables in which American diplomats refer to candid British views of key figures in the Muslim world.
According to The Mail Today, 92-year-old Nelson Mandela, former President of South Africa is among world leaders believed to have been criticised in a leak of US diplomatic files.
Other world leaders who have clashed with the US, including Afghanistan's Hamid Karzai, Libya's Colonel Gaddafi and Zimbabwe's Robert Mugabe, also come off badly in the no-holds barred private cables to the White House from scores
About 800 messages are from the US Embassy in London and some reportedly feature negative and hostile comments
about Brown and the Labour Government. These are thought to relate to the Anglo-US dispute after Britain freed Lockerbie bomber Abdelbaset Ali Mohamed al Megrahi from a Scottish jail to a hero's welcome in Libya last year.
The cables are believed to include withering US assessments of Brown's personality and prospects of staying in power. Cameron also does not escape from criticism.
Mandela, who stepped down as President in 1999, condemned George Bush over the Iraq War, suggesting the US President had ignored the United Nations' calls for restraint because the then UN Secretary-General Kofi Annan was black.He also called Tony Blair the "foreign minister of the United States" for supporting Bush over Iraq. The secret cables, due to be published online on Sunday, are believed to be from January 2006 to December 2009 - taking in the latter part of Blair's premiership and most of Gordon Brown's.
The report quoted defence insiders to say Britain's national security could be "put at risk" by the revelations, which are understood to include details of the Iraq and Afghan wars plus information about secret service practices and intelligence sources.
The British government has issued a DA-Notice (defence advisory), warning newspapers that publishing the secrets could compromise national security. "We would condemn any unauthorised release of this classified information just as we condemn leaks of classified material in the UK. They can damage national security, are not in the national interest and, as the US has said, may put lives at risk," the foreign office said.