Buckingham Palace has confirmed US President Barack Obama will come to the UK on a state visit in May.
It is the first state visit by a US president since that of President George W Bush and his wife, Laura, in 2003.
President Obama came to the UK for the G20 summit in 2009 but that was not a state visit.
In July last year David Cameron visited Washington and met Mr Obama, who will visit London from 24 to 26 May.
The First Lady, Michelle Obama, will accompany the president on the two-day visit but details of his itinerary have not been announced.
The prime minister's official spokesman said on Thursday: "The prime minister is very pleased this visit is taking place. It is a sign of the strong and enduring relationship between our two countries."
A state visit is a formal affair when a visiting head of state is according full ceremonial trappings and is hosted by the Queen.
http://www.bbc.co.uk/news/uk-politics-12497265