Donald Trump has taken to Twitter to demand that Germany "pay more" to the United States for its defense, only hours after meeting with Angela Merkel.

Mr Trump and the German Chancellor sat down together in The Oval Office for the first time yesterday and included discussions of America's terms for its continued commitment to Nato.

Mrs Merkel told the president she believed Germany must work to pay its fair share to be in the alliance – a key demand by Mr Trump, who has repeatedly said he believes America is bearing the brunt of the costs.