The president will be joined in London by First Lady Michelle Obama and they will have lunch Friday with Queen Elizabeth II - a day after her 90th birthday

Air Force One touched down at Stansted Airport shortly after 9.30pm on Thursday after visiting Saudi Arabia where Obama held talks with King Salman

He was then ushered into the presidential helicopter Marine One before being taken from the airport

The president will use his visit to try and persuade British voters not to ditch their membership of the European Union ahead of a June 23 referendum.

He will be joined in London by First Lady Michelle Obama and they will have lunch Friday with Queen Elizabeth II - a day after her 90th birthday.

The pair will also attend a dinner hosted by Prince William, his wife, Kate, and Prince Harry at Kensington Palace.

Obama is expected to speak out in opposition of Britain's exit from the European Union as he meets with Cameron on Friday.

His visit is a welcome one for Prime Minister David Cameron, who is leading the 'In' campaign.

However, it has drawn scorn from those arguing that Britain should leave the EU.