The UK and US are at a "pivotal moment" in their relationship and "profound challenges" lie ahead, US President Barack Obama has told MPs and peers in Westminster on 25 May 2011

In a historic speech to both Houses of Parliament in Westminster Hall, the president said the special relationship between the two nations was founded not only on shared history and language but common beliefs and values "that have united our people through the ages".

Rejecting arguments that emerging superpowers like China, India and Brazil meant the end for American and European influence in the world, he stressed the time for European and US leadership was "now", in a speech that covered a range of issues including foreign policy, economic development and international security.

President Obama praised the role of the UK in spreading the ideals of democracy around the world, quoting Sir Winston Churchill, who said the Magna Carta, Bill of Rights, habeas corpus, trial by jury and common law "find their most famous expression in the American Declaration of Independence".

Spontaneous applause broke out in the hall when Mr Obama said it was the acceptance of diversity in countries like the UK and US that makes it possible "for the grandson of a Kenyan who served as a cook in the British army to stand before you as president of the United States".

It is rare for a foreign head of state to address both Houses of Parliament in Westminster Hall.

Last September Pope Benedict became the third visiting dignitary to address both Houses in Westminster Hall since World War II. He followed Nelson Mandela in 1996, when he was South African president, and French president Charles de Gaulle in 1960.