Mr Bush revealed the extent of his religious fervour when he met a Palestinian delegation during the Israeli-Palestinian summit at the Egpytian resort of Sharm el-Sheikh, four months after the US-led invasion of Iraq in 2003.

One of the delegates, Nabil Shaath, who was Palestinian foreign minister at the time, said: "President Bush said to all of us: 'I am driven with a mission from God'. God would tell me, 'George go and fight these terrorists in Afghanistan'. And I did. And then God would tell me 'George, go and end the tyranny in Iraq'. And I did."

Mr Bush went on: "And now, again, I feel God's words coming to me, 'Go get the Palestinians their state and get the Israelis their security, and get peace in the Middle East'. And, by God, I'm gonna do it."

Mr Bush, who became a born-again Christian at 40, is one of the most overtly religious leaders to occupy the White House, a fact which brings him much support in middle America.

Soon after, the Israeli daily newspaper Haaretz carried a Palestinian transcript of the meeting, containing a version of Mr Bush's remarks. But the Palestinian delegation was reluctant publicly to acknowledge its authenticity.

The BBC persuaded Mr Shaath to go on the record for the first time for a three-part series on Israeli-Palestinian diplomacy: Elusive Peace, which begins on Monday.

Religion also surfaced as an issue when Mr Bush and Tony Blair were reported to have prayed together in 2002 at his ranch at Crawford, Texas - the summit at which the invasion of Iraq was agreed in principle. Mr Blair has consistently refused to admit or deny the claim.

Mahmoud Abbas, the Palestinian prime minister, who was also part of the delegation at Sharm el-Sheikh, told the BBC programme that Mr Bush had said: "I have a moral and religious obligation. I must get you a Palestinian state. And I will."

Mr Shaath's comments came as Mr Bush delivered a speech yesterday aimed at bolstering US support for the Iraq war.

He revealed that the US and its partners had disrupted at least 10 serious al-Qaida plots since September 11, including three planned attacks in the US. "Because of this steady progress, the enemy is wounded - but the enemy is still capable of global operations," he said. He added that Islamic radicals had used a series of excuses to justify their attacks, from conflict with the Israelis to the Crusades 1,000 years ago.

"We're facing a radical ideology with unalterable objectives: to enslave whole nations and intimidate the world," he said.

He conceded that al-Qaida, led in Iraq by Abu Musab al-Zarqawi, and other insurgents had gained ground in Iraq but the US would not leave until security had been established. "Some observers also claim that America would be better off by cutting our losses and leaving Iraq now. This is a dangerous illusion, refuted with a simple question: Would the United States and other free nations be more safe, or less safe, with Zarqawi and Bin Laden in control of Iraq, its people, and its resources?" Mr Bush asked.