President Obama hails 'special relationship' at banquet
US President Barack Obama has hailed his country's "special relationship" with the UK in a speech delivered at a state banquet at Buckingham Palace.
He thanked the UK for its solidarity since 9/11 and 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 and attended by royalty, politicians and film stars.
It came 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, as well as former prime ministers Gordon Brown, Tony Blair and Sir John Major.
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.
The Queen opened proceedings by telling Mr Obama and his wife Michelle that she was "so glad" they were visiting the UK again.
She said: "I firmly believe that the strength of our links and many shared interests will continue to ensure that, when the US and the UK stand together, our people and other people of goodwill around the world will be more secure and can become more prosperous."
She proposed a toast to "celebrate the tried, tested - and, yes, special relationship between our two countries".
The president then told the guests: "As we approach the 10th anniversary of 9/11, I'm particular grateful for the solidarity that the United Kingdom has shown to America over the past decade.
"From that day to this you have been our closest partner in the struggle to protect our people from terrorism attacks and violent extremism from around the world despite very heavy sacrifices here."
To conclude, the president proposed a toast to the Queen, but there appeared to be a mistake as the band played the opening bars to God Save the Queen before he had finished.
The Obamas arrived in London on Monday night from the Republic of Ireland, a day ahead of schedule because of the threat of disruption from the volcanic ash cloud.
On Tuesday, the president and his wife joined the Queen at Buckingham Palace where they briefly met the Duke and Duchess of Cambridge before moving to the palace gardens for a ceremonial welcome, including a 41-gun salute.
The presidential pair's visit to Westminster Abbey included an impromptu meeting with choirboys, when Mr Obama was teased by his wife for his lack of singing talent.
Mr Obama briefly met the prime minister in Downing Street ahead of talks on Wednesday. They then left together for a surprise visit to the Globe Academy in Southwark, south London, where they teamed up for a table tennis match against schoolboys.
The leaders' talks on Wednesday are likely to focus on the Middle East and the ongoing conflict in Libya.
The day's itinerary will also include a barbecue at Number 10 with British and American military veterans and a speech about US foreign policy to MPs before a return banquet at Winfield House, where the Queen will formally say farewell.
In a joint article in the Times on Tuesday, Mr Obama and Mr Cameron said of their countries' relationship: "Ours is not just a special relationship, it is an essential relationship - for us and for the world.
"When the United States and Britain stand together, our people and people around the world can become more secure and more prosperous.
"The reason it thrives is because it advances our common interests and shared values. It is a perfect alignment of what we both need and what we both believe."
They also vowed not to abandon the protesters fighting for democracy in Arab countries, writing that they would "stand with those who want to bring light into dark, support those who seek freedom in place of repression, aid those laying the building blocks of democracy".
"We will not stand by as their aspirations get crushed in a hail of bombs, bullets and mortar fire.
"We are reluctant to use force, but when our interests and values come together, we know we have a responsibility to act."