The exam, which the US president described as a six-month physical, was his fourth publicly disclosed medical exam since he returned to office for a second term.

The 79-year-old president spent more than three hours at Walter Reed National Military Medical Centre for what the White House described as preventive medical and dental checkups.

President Donald Trump announced the nomination on social media amid pressure from Congress to name a permanent replacement for Tulsi Gabbard, who resigned last month.