Next week a titan on the world stage will fly across the Atlantic to spend Wednesday talking war and peace with President Bush and making his mark on the American people.

Unfortunately for Gordon Brown, an awkward coincidence of timing means that his final visit to President Bush coincides with Pope Benedict XVI’s first to the United States, only the second time a pontiff has ever gone to the White House. Washington residents are already preparing for motorcade gridlock.

With a programme that includes a public Mass in the 40,000-seat National Park baseball stadium, the first nonsporting event in the new park, there seems little doubt which new arrival will be gripping the imagination more.

By contrast, Mr Brown’s agenda for his four-day, three-city trip – the economy and international financial stability, meetings with Wall Street bankers and discussions about the future of Africa – will never compete for the popular affection of the American people, despite recent attempts.

On Wednesday night the Prime Minister unleashed his fixed grin on an unsuspecting TV audience when he appeared on American Idol to pledge £200 million of mosquito nets for Africa, prompting one American newspaper to suggest he was a “parody of himself”.

Grover Norquist, the head of an American think-tank with close connections to the White House, said: “Most Americans are not aware of Mr Brown, and most Republicans in Washington are not aware of any change in the special relationship other than Tony Blair, a pal, has left. There is more buzz about the arrival of the Pope next week.”

Government figures are already nervous about seeing Mr Brown out of the country and appearing with President Bush so close to England’s local elections. Others in the party are more philosophical. “He can’t stop being Prime Minister just because there are local elections on,” one said.

Mr Brown will also use a big speech on Friday at the Kennedy library in Boston to urge the United States to reengage with the world in the way it did after the Second World War.

He will say the world is at a point in history when it needs American “values and leadership”. Downing Street says that there are no plans for the Presbyterian Mr Brown to meet the Pope.

The most eagerly anticipated part of the trip, however, will be the meetings that Downing Street says have been arranged with the three presidential candidates. After subtly distancing himself from President Bush, Mr Brown will be seeking to reaffirm Britain’s ties to the United States by seeing the Democrat contenders, Barack Obama and Hillary Clinton, as well as the Republican John McCain, whom he met last month. Downing Street says the meetings will take place behind closed doors and diplomatic conventions mean the Prime Minister will say little about their contents.

When the trip was arranged, no one in Downing Street expected the Democratic nomination still to be open. Mr Brown will have to negotiate his way through the tensions of the Clinton-Obama race without signalling favouritism, despite a longstanding relationship with Mrs Clinton.

But even this has risks. Downing Street could face disenchantment if there are last-minute complications because of the pressures of the campaign on the two Democrat contenders. Mr Obama and Mrs Clinton are expected to go head-to-head in a critical TV debate the night before the Pennsylvania primary on April 22.

Should either pull out of a meeting with the British PM, Mr Brown will once again be reminded that he does not have the pulling power in the United States of either his predecessor or, it seems, the Pope.

Their itineraries

The Prime Minister

Tuesday Arrive in New York
Wednesday UN Security Council meeting with senior business figures. Fly to Washington, British Embassy reception. Sarah Brown at private dinner
Thursday Meet President Bush at White House; press conference. Meetings with Clinton, Obama and McCain. Private dinner at White House
Friday Fly to Boston; speech at Kennedy library
Saturday Arrive home

The Pope

Tuesday Arrive at Andrews Air Force Base, greeting by President Bush
Wednesday Join President and First Lady at White House. Private prayer for 350 US bishops
Thursday Mass at baseball’s Nationals Park, Washington. Address Catholic University of America
Friday Fly to New York, address United Nations
Saturday Visit World Trade Centre
Sunday Mass at Yankee Stadium. Fly back to Vatican

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