US President Joe Biden said he dropped out of his re-election bid because he feared that the intraparty battle over his candidacy would be a “real distraction” for Democrats and that his highest priority was to defeat Donald Trump in November.

In his first interview since quitting the race, Biden, 81, said he had “no serious problem” with his health. He blamed his poor debate performance on being sick at the time, brushing off any concern about his age, reports the BBC.

The US president pledged to campaign for Kamala Harris saying he was going to do whatever his vice-president “thinks I can do to help most”.

“We must, we must, we must defeat Trump,” he told US broadcaster CBS News. Biden said if he had continued his campaign, the presidential contest would have gone “down to the wire”.