Host Colin Jost (left), Joe Biden and NBC News White House senior correspondent Kelly O'Donnell attend the White House Correspondents' Association Dinner in Washington, US, on Saturday. Retuers

US President Joe Biden delivered an election-year roast on Saturday night at the annual White House Correspondents' Association dinner as protesters outside criticized his support for Israel's war against Palestinian group Hamas.

Biden used the annual black-tie event to chide his Republican rival Donald Trump for immaturity, poke fun at his own advanced age and take on the Washington press corps.

"Yes, age is an issue. I'm a grown man, running against a 6-year-old," Biden joked.

Biden, 81, later added of former President Trump, 77: "Age is the only thing we have in common. My vice president actually endorses me."

Trump reacted to the event by calling it "really bad" in a post on his Truth Social platform. "Crooked Joe was an absolute disaster! Doesn’t get much worse than this!" he said.

Demonstrators holding banners outside the gathering at the Washington Hilton chanted about journalists' deaths in Gaza. Hundreds of protesters encouraged journalists to boycott the annual event and shouted down administration officials as they entered.

Joe Biden greets US comedian Colin Jost (right) at the Washington Hilton, in Washington, DC, on Saturday. AFP

Biden avoided the large protests at the front of the hotel by arriving through a back entrance, where he was greeted by smaller groups of protesters calling for a ceasefire.

At the century-old event, often referred to as Washington's "nerd prom," hundreds of journalists, politicians and celebrities rubbed elbows in a massive banquet hall. It often features friendly jabs from the president in a closing speech that takes aim at reporters and other guests in the audience.

Biden offered some advice to the press corps.

"I'm sincerely not asking you to take sides. I'm asking you to rise up to the seriousness of the moment. Move past the horse race numbers and the gotcha moments and the distractions, the sideshows that have come to dominate and sensationalize our politics, and focus on what's actually at stake," Biden said.

Reuters