Publicly, both sides will portray the midday encounter at the Vatican as a fence-mending exercise after the Pope’s criticism of the US intervention. The Pope is expected to approve the coalition’s plans to return sovereignty to Iraq.

But privately, the 84-year-old pontiff intends to take Mr Bush to task over the war and what he considers an even more disastrous postwar occupation involving unnecessary deaths, torture and violation of the rule of law.

“Bush is in for a dressing down, which could play badly with Catholic voters if it emerges in public,” a Vatican insider told The Times.

“Bush is taking a gamble. There will be a lot of talk about common ground on humanitarian relief and self-government in Iraq, and the need to move forward. There will also be a papal rebuke for the loss of life and the mistreatment of Iraqis.”

The Pope will also press Mr Bush to take “serious steps” to restart the Middle East peace process and increase development aid to Africa.

How much of this will become public remains to be seen, but with more than 60 million Roman Catholics in America and a Catholic running against him in November’s election, Mr Bush will be hoping little gets out.

The Vatican issues an official account of the Pope’s talks with world leaders which is pored over for signs of what was said behind the scenes. Reporters are allowed in at the beginning and the end of talks, but the encounter itself is strictly private.

Mr Bush will be accompanied by his wife, Laura, Colin Powell, the US Secretary of State, and Condoleezza Rice, the National Security Adviser, at today’s meeting — the third between the two men.

In a snub to Mr Bush, the Vatican initially told the White House that the Pope, who is in frail health, would be unable to see the President.

The Pope is travelling to Switzerland tomorrow for a two-day visit, his first abroad since a tiring journey to Slovakia last September, when he alarmed followers by being unable to read speeches.

He has since revived enough to travel again, but aides told the Bush Administration that the Pope needed to conserve his strength and had no gap in his schedule.

The White House altered Mr Bush’s travel plans, arranging for him to fly through the night to ensure that he arrived at the Vatican in time.

The newspaper Il Messaggero said that Mr Bush was bound to be lectured by an “anti-war Pope” who had publicly condemned torture last week as an intolerable affront to human dignity, a clear reference to the Abu Ghraib abuses. Cardinal Pio Laghi, a former papal ambassador to the US, said that the Pope would rebuke Mr Bush for failing to heed his warnings not to go to war. “Now one can see just how wise those warnings were. We are on the edge of an abyss. The struggle against terrorism does not justify abandoning the rule of law. The means do not justify the end”.

He said that the Bush Administration had shown a “surprising lack of understanding of the Islamic world” and an arrogance and insensitivity which was not representative of “America as a whole”.

Vatican watchers said that the trip was reminiscent of Tony Blair’s visit to the Vatican in February last year when the Pope urged him to “avert the tragedy of a war, which according to many people is still avoidable”.

Mr Bush told Italian television this week that the Pope was “a great man”. He said that he understood anti-war protests, saying that he did not like war himself. But Saddam Hussein had posed a threat to peace, and he had taken “a very difficult decision” after trying “all possible diplomacy”, with war as a last option.

Archbishop Giovanni Lajolo, the Vatican’s Foreign Minister, said last month that the abuse of Iraqi prisoners at Abu Ghraib was “a more serious blow to the United States than September 11” and would foment further anti-Western hatred in the Islamic world.

JOHN-PAUL'S WORDS ON WAR

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