Barack Obama and David Cameron
Prime Minister David Cameron and US President Barack Obama will give a joint conference later this monthReuters

US President Barack Obama will offer his "very candid view as a friend" that the UK is better off in the EU when he visits next week. During his UK visit, Obama will speak with youth at a town hall, have lunch with Queen Elizabeth II at Windsor Castle to celebrate her 90th birthday and stage a joint conference with David Cameron at 10 Downing Street between 21- 24 April.

The visit will be his last to the UK during his presidency and he will also visit Saudi Arabia and Germany. He will throw his weight behind Cameron's efforts to keep Britain in the EU.

Senior US officials said Obama believed it was up to the citizens of the UK to decide their future, but he would offer his opinion "if asked". As official campaigning ahead of the EU referendum kicks off, Obama could come under strong criticism from the Leave camp, who previously accused him of hypocrisy. Last month London Mayor Boris Johnson said: "There is no country in the world that defends its own sovereignty with such hysterical vigilance as the United States of America."

But Obama's deputy National Security Advisor insisted the president "will offer his view if he is asked". Ben Rhodes added: "He will make it clear it is a decision for the people of the UK to make, not ours.

"I am sure he will have plenty of opportunities to be asked this question. He will be very candid as friend that it is important for the UK to remain in the EU."

Rhodes added that the White House wants the UK to be economically strong as part of the EU. He added: "If he is asked his views as a friend, he will offer it. But he will make it clear that it is something for the British people to decide."

Obama will also meet with King Salman in Saudi Arabia. He will also attend a summit with the leaders of Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates (UAE) to discuss combating the Islamic State (Isis).

In Germany, the president has planned talks with Chancellor Angela Merkel. He will also open the Hannover Messe, one of the world's largest industrial technology trade fairs with Merkel.