US President-elect Joe Biden has fractured his foot while playing with one of his dogs, his doctor has said.

Mr Biden, 78, twisted his ankle on Saturday when he slipped while with Major, one of his two German shepherds.

The Democrat visited an orthopaedist in Newark, Delaware, a day later “out of an abundance of caution”.

His personal physician, Kevin O’Connor, said initial x-rays did not show an “obvious fracture”, but ordered a more detailed CT scan.

The subsequent scan found that Mr Biden had suffered “hairline fractures” of two small bones in the middle of his right foot, the doctor said.

“It is anticipated that he will likely require a walking boot for several weeks,” Mr O’Connor said.

Mr Biden, who turned 78 earlier this month, will become the oldest US president to take office after he’s inaugurated on 20 January next year.

Given this, Mr Biden’s health is expected to be watched closely by allies and opponents.

His doctor described him as “healthy, vigorous” and “fit to successfully execute the duties of the presidency” in a medical report released last December.

Mr Biden is set to bring his two German shepherds – Champ and Major – with him to the White House.

The president-elect and his wife, Jill Biden, fostered Major from a dog shelter in Delaware and made his adoption official in November 2018.

Champ lived with the Bidens on Capitol Hill in Washington DC during Barack Obama’s presidency, when the former senator for Delaware was vice-president.