US President Joe Biden has announced that he will seek re-election for the presidency in 2024.

Now 80 and already the oldest president in US history, Biden had long signalled he would run for another four-year term.

In a video to launch his bid to retain the White House, he cast the next election as a fight for democracy and personal freedom, saying: “Let’s finish the job.”

Donald Trump has already launched his bid to return to the White House, meaning the pair could be set for a rematch of the 2020 election in November next year.

However an NBC News poll recently found that 70 percent of Americans, and just over half of Democrats, believe he should not run again.