US vice president Kamala Harris assumes presidency as Biden undergoes surgery

US vice president Kamala Harris will serve as acting president while President Joe Biden is under anaesthesia for a routine colonoscopy, the White House has said.

“As was the case when President George W Bush had the same procedure in 2002 and 2007, and following the process set out in the Constitution, President Biden will transfer power to the Vice President for the brief period of time when he is under anaesthesia,” White House Press Secretary Jen Psaki said in a statement. “The Vice President will work from her office in the West Wing during this time.”

Mr. Biden arrived at the Walter Reed Medical Centre on Friday for his annual physical, his first while serving as president.

Ms. Psaki added that the White House will release a report on Mr. Biden’s health later on Friday. The physical was not initially on the public presidential schedule but was announced hours before Mr Biden left the White House at around 8.30am. He arrived at the hospital in Maryland at 8.51am.

Mr. Biden, who turns 79 on Saturday, is the oldest person in US history to hold the office of president.

Before Mr. Biden, Mr. Trump was the oldest president in history at the time of his swearing-in. Mr. Trump was 70 years old when he took office in January 2017. Fellow Republican President Ronald Reagan was the oldest before Mr. Trump. Mr. Reagan was 69 when he took office in 1981 and 77 when he left office in 1989. Mr. Biden took office at the age of 78.

Ms. Harris, who is the first woman to serve as vice president, is also the first woman to wield presidential power.

Following concerns about Mr. Biden’s age, the administration has said on numerous occasions that he would undergo a physical this year and that the results would be public.