President Obama arrives in UK to give PM a helping hand over Brexit (oh, and he's going to meet the Queen as well)

The president (left, arriving in London) will also use his visit to try and persuade British voters not to ditch their membership of the European Union ahead of a June 23 referendum. 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. Obama is likely to suggest Britons should vote to stay in the bloc to preserve Britain's wealth, its 'special relationship' with the United States and the cohesion of the West. 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. The president touched down in Air Force One (inset) at around 9.30pm on Thursday. He was then transferred onto his private helicopter - Marine One (right) - on which he was flown to Winfield House, the U.S. Ambassador's residence, where he will stay in London.