President Joe Biden has worn a Donald Trump cap on a visit to a fire station in Pennsylvania.

Footage of  him sporting the hat at Shanksville Fire Station in the battleground state went viral online.

The White House said he was given it by a Trump supporter who persuaded him to wear it in a spirit of unity.

The president had said the bipartisan unity seen after 9/11 needed to return to the US, which has become increasingly polarised in recent years.

Andrew Bates, White House senior deputy press secretary, wrote on X: “@POTUS spoke about the country’s bipartisan unity after 9/11 and said we needed to get back to that.

“As a gesture, he gave a hat to a Trump supporter who then said that in the same spirit, POTUS should put on his Trump cap. He briefly wore it.”