Barack Obama is expected to urge Britain to remain in the EU when he visits London later this week.
The American president will arrive in the UK from Saudi Arabia late on 21 April and will meet with Prime Minister David Cameron and have lunch with the Queen the following day.
Mr Obama is due to discuss counter-terrorism measures with the PM, but the former Work and Pensions Secretary Iain Duncan Smith has suggested Mr Cameron also wants the president to help “bully the British people” into remaining in Europe.
On 23 April, Mr Obama will field questions from young people and speak about the special relationship between the UK and the US at a town hall event, where it is also expected he will be asked about his views on June’s EU referendum.
Ben Rhodes, the president’s deputy national security advisor, says Mr Obama supports a strong UK in the EU.
“For us the UK is a key partner and the EU is a key partner”, he said. “We believe all of us benefit when the EU can speak with a strong single voice and can work with us to achieve prosperity. We believe the US benefits from a strong UK economy”.