Trump news – live: Witnesses describe 'improper' Ukraine call as president mocks veteran's military uniform

Donald Trump’s personal physician, Navy commander Sean Conley, has written a letter insisting the president’s unannounced Saturday visit to the Walter Reed National Military Medical Center in Bethesda, Maryland, was “a routine, planned interim checkup”.

“Despite some of the speculation, the president has not had any chest pain, nor was he evaluated or treated for any urgent or acute issues,” Commander Conley wrote in his statement, issued by the White House in a bid to dispel rumours that a more serious health complaint was being covered up.

Four key witnesses are due to appear before the House impeachment inquiry on Tuesday to testify on the Ukraine scandal – Alexander Vindman, Jennifer Williams, Kurt Volker and Tim Morrison – after the US Supreme Court blocked the release of Mr Trump’s tax returns to Congress.

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