In a speech delivered at a state banquet at Buckingham Palace on Tuesday he thanked the UK for its solidarity since 9/11 and cooperation in tackling the security threats that have followed.

He also paid tribute to the UK's military forces for "standing shoulder to shoulder with the US for decades".

The banquet was hosted by the Queen at the end of a packed first day of the president's state visit.

The banquet was attended by all three main political leaders, Prime Minister David Cameron, Deputy Prime Minister Nick Clegg and Labour leader Ed Miliband, and former prime ministers Gordon Brown, Tony Blair and Sir John Major, as well as royalty and film stars.

Other famous names seated around the horseshoe-shaped table included former athlete and politician Lord Coe, actors Tom Hanks and Kevin Spacey, actress Helena Bonham Carter, entrepreneur Sir Richard Branson and London Mayor Boris Johnson.

The 170 or so guests dined on new season lamb, roast potatoes and a vanilla charlotte, accompanied by vintage champagne.