Mr Bush announced last week he was prepared to meet a small group of families of the British war dead. The names have not been officially revealed but two of the invited families have come forward to talk exclusively to the IoS, saying they will challenge the US President to explain why he went to war without a United Nations mandate and why no chemical and biological weapons have been found.
Lianne Seymour, whose husband, Commando Ian Seymour, was killed in a helicopter crash at the outbreak of the war, welcomed the chance to meet Mr Bush. But she dismissed his claim that the 53 Britons killed so far in Iraq had died in a good cause. She said: "Bush has been suggesting that he's going to put our minds at rest. He suggests our husbands' lives weren't lost in vain. However, I'm going to challenge him on it.
"They misled the guys going out there. You can't just do something wrong and hope you find a good reason for it later. That's why we have all the UN guidelines in the first place."
Another relative, Tony Maddison, whose stepson Marine Christopher Maddison was killed, allegedly by friendly fire, during a battle near Basra, said: "I'm beginning to feel Mr Blair has been a puppet, so I'm looking forward to meeting Bush, to ask: 'What are you doing to our Prime Minister? Look what he's doing to our country.'"
Mr Maddison and his wife, Julie, suspect that the spectre of Iraq's weapons of mass destruction was raised to "frighten" the country into war, although they think it was right to topple Saddam. "We've gone to war for the wrong reasons," he said. "I'm still hoping that weapons of mass destruction will be discovered, but I'm beginning to think we were being lied to."
Details of Mr Bush's meeting with the families are being kept secret for security reasons, but it is expected to take place at the end of the week at an undisclosed location in London.
The three-day state visit this week will be met by an unprecedented security operation. About 5,000 police officers and 250 US secret service agents will guard the President and cover a series of protests being planned. The scale of the antipathy many Britons feel towards Mr Bush was revealed last night by a YouGov poll in which 60 per cent of those questioned branded him a threat to world peace.
In a significant about-turn, the police are expected to allow the largest march, on Thursday, to go past Downing Street and Parliament in a bid to avert violent clashes with hardline demonstrators.
Among the marchers will be the sister of Lieutenant Philip Green, a Royal Navy helicopter pilot killed in a crash in the Gulf. Juliet McGrory, whose father, Richard Green, has fiercely attacked the war, said: "Bush says my brother died for a 'noble cause', which, after the pain of recent months, I find an incredible statement. I don't understand how killing innocent civilians can possibly be described as a 'noble cause'. The trip is nothing more than a masquerade and a PR opportunity."
The state visit can hardly have come at a worse time for Mr Bush, with polls in the US showing that public confidence over his ability to deal with the problems in Iraq is falling. For the first time, more than 50 per cent have said they "disapprove" of the way he is handling the situation.
The trip threatens to be a PR disaster for the President and his officials have tried - apparently in vain - to ensure that is he kept as far away from demonstrators as possible.
Asked this week about the protesters he will encounter in the capital, Mr Bush said: "I don't expect everybody in the world to agree with the positions I've taken. I'm so pleased to be going to a country which says that people are allowed to express their minds. That's fantastic. Freedom is a beautiful thing."
Quite how his meeting the families of British servicemen killed in Iraq will be perceived at home is unclear: the President has not attended the funerals of any of the American troops killed. Nor has he visited any of the thousands of injured troops who have returned to the US.