US Vice-President Kamala Harris will become the first woman to briefly be given presidential powers as Joe Biden undergoes his annual health check.

President Biden will transfer power to Ms Harris for the period in which he is placed under anaesthesia for a routine colonoscopy on Friday.

The medical examination will be Mr Biden's first as president and comes on the eve of his 79th birthday.

Ms Harris will temporarily take control of the US military and nuclear weapons.

"The vice-president will work from her office in the West Wing during this time," White House Press Secretary Jen Psaki said in a statement.

The 57-year-old Ms Harris is the first woman to be elected US vice president.