Nelson Mandela expressed fury to the British government over Britain's decision to join with the Americans in invading Iraq, it emerged yesterday.
The former South African president picked up the phone and called London to spell out his anger about the decision to join the US-led mission to topple Saddam Hussein.
He might be famed for his politeness, but in an extraordinary call to a member of Mr Blair's Cabinet, Peter Hain, Mr Mandela's angry feelings boiled over.
Diplomatic niceties were abandoned as he warned that Britain's reputation around the world would suffer "huge damage" because of the invasion and that all the Blair administration's good work in Africa would be forgotten.
Details of the call are disclosed in a new biography of Mr Mandela by Mr Hain, a long-standing friend who was Welsh Secretary at the time.
Mr Hain recalled: "He said: 'A big mistake, Peter, a very big mistake. It is wrong. Why is Tony doing this after all his support for Africa? This will cause huge damage internationally'."
He said last night that he had never encountered his old friend as angry as he was during that conversation: "He was virtually breathing fire down the phone on this and feeling a sense of betrayal."
He went on: "It wasn't a pre-planned call that I had been expecting. He was just put through by Downing Street. Because we were friends he was probably more frank with me than he would have been if he had been speaking with a prime minister or president."
Mr Hain added that Mr Mandela was particularly distressed and frustrated because he was an admirer of the Blair government's record in Africa, where it intervened in Sierra Leone, increased aid and campaigned for a ban on landmines.
"He just felt that all of this had been completely blown out of the water by the Iraq invasion," Mr Hain said. "It did not surprise me because many people felt the same way. I knew that the sort of constituency in Britain and the world that Nelson Mandela naturally spoke for felt that we had made the wrong decision.
"He is a supremely polite and diplomatic person, but at the same time very independently minded."
Mr Hain said: "I listened very carefully to what he had to say and I explained that I thought Tony was acting out of conviction."
The former minister said he relayed Mr Mandela's comments to Downing Street – and told Mr Blair in person about the tirade. "They knew the government was being assailed with criticism on all sides. It was one that was added to the pile," he said.
Mr Blair does not mention any such protests in his memoirs, maintaining that he got on well with Mr Mandela because he "treated him as a political leader, not as a saint".
Mr Mandela, a Nobel Peace laureate, was an outspoken critic of the war at the time, arguing that the sole reason for the US military action was to gain control of Iraq's oil reserves. He also ridiculed Mr Blair as the "US foreign minister" rather than the British Prime Minister.
Mandela: The Story of a Universal Hero, which includes a tribute by Mr Blair, is published today by Spruce.