WASHINGTON (AFP) ― British Prime Minister David Cameron arrived in Washington Tuesday, to back President Barack Obama’s bid to cool “loose talk” over war with Iran and as Afghan war policy faces sharp scrutiny.

Cameron became the first foreign leader to join Obama on Air Force One as the two leaders headed off to watch a college basketball game in Ohio, in a gesture meant by the White House to highlight a bond between the two men.

The meat of the visit will come Wednesday as Obama welcomes Cameron to Oval Office talks, the two leaders hold a press conference and enjoy the pageantry of a state dinner at the White House.

Cameron’s arrival comes at a moment of extreme stress for the NATO-led mission in Afghanistan, following a string of incidents which culminated in a massacre of civilians on Sunday by a renegade U.S. soldier.

Both sides say they are committed to a timetable which would see the last Western combat troops withdrawn from the country at the end of 2014, but there is rising debate about the pace of the drawdown.

Obama warned Monday against a “rush for the exits” in Afghanistan, making the case that the soldier’s murderous rampage which killed 16 civilians, mostly women and children, should not throw U.S. strategy off course.

British Ambassador to Washington Sir Peter Westmacott signaled that Cameron would take a similar tack in his meetings with Obama.

“I don’t have the impression from the responses from any of the governments, from the authorities concerned, that these terrible incidents knock the strategy of course,” Westmacott told reporters.

But behind the scenes, there is a growing impression that Obama, and some of his Western allies, facing declining public support for the war, are keen to promote a quicker drawdown than military brass might want.

The New York Times reported Tuesday the White House could reduce the U.S. footprint in Afghanistan by an additional 20,000 troops next year.

In a joint Washington Post article, the two leaders said they would prepare the NATO summit in Chicago in May, which will including “shifting to a support role” and ensuring Afghanistan is never again a haven for al-Qaida.

Cameron’s trip comes in the week following a crucial visit to Washington by Israeli Prime Minister Benjamin Netanyahu dominated by the possibility that Israel could mount a unilateral strike against Iran in the coming months.

“Both of our governments have made clear that we don’t think that would be helpful,” said Westmacott.

Washington does not believe the time is ripe for such an attack, though stressed Israel’s right to defend itself and warned that it could take military action to forestall an Iranian bomb at a later date.

The two leaders will also discuss their failure to stop the Syrian President Bashar al-Assad’s slaughter of his own people, though will have few illusions about the chances of a new U.N. Security Council resolution.

Cameron was accompanied by his wife Samantha, on what British officials said was her official trip abroad with her husband and brought a high-powered delegation including Chancellor of the Exchequer (finance minister) George Osborne.

Obama needs no encouragement to indulge his passion for basketball, and gave Cameron a chance to sample a slice of American life by taking him to a first-round game in the annual U.S. college basketball tournament “March Madness”

in Dayton, Ohio. They will see the Western Kentucky University Hilltoppers, the only team in the event with a losing record at 15-18, face Mississippi Valley State’s Delta Devils, who went 21-12.

Cameron’s spokeswoman said that “the prime minister appreciates basketball” though he is hardly known as a hoops aficionado.

Some commentators have wryly commented that Obama’s trip will likely get him front-page coverage in newspapers on Wednesday in Ohio, a swing state that forms a vital plank of his strategy to win a second term in November’s election.

Cameron is shadowed on the trip by his own political concerns.

Reports said that British police probing phone hacking arrested former Rupert Murdoch aide Rebekah Brooks and her husband Charlie, a close friend of the prime minister earlier on Tuesday.

Socialites in Washington were meanwhile looking forward to the state dinner, with reports suggesting that U.S. Open golf champion Rory McIlroy from Northern Ireland could be on the closely guarded guest list.