(Adds Trump's response in paragraph 5)

    By Jarrett Renshaw

       WASHINGTON, April 27 (Reuters) - U.S. 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 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.

    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.

    This year, the event was hosted by "Saturday Night Live"

cast member Colin Jost.

    Grassroots movement CODEPINK marched to the venue from a

nearby park. "The United States media perpetuates

anti-Palestinian narratives and ignores Israeli war crimes," the

group said on its website.

    A growing movement against the war in Gaza has dogged Biden

this year including at a $250-per-ticket March fundraiser at New

York's Radio City Music Hall that was disrupted by protesters.

    Recently, that movement has expanded to college campuses in

the U.S., signifying a growing revolt inside the Democratic base

that Biden needs to defeat Trump, who is now the Republican

frontrunner.

    Kelly O'Donnell, president of the White House

Correspondents' Association, declined to comment on security

measures for the dinner.

    "The safety and security of our protectees is the U.S.

Secret Service's top priority," said U.S. Secret Service

spokesperson Alexi Worley, who declined to comment further.

    Israel's six-month old war against Hamas in Gaza, in

response to the Oct. 7 attack by the militant group in southern

Israel, has killed more than 34,000 people, Palestinian health

authorities say, and caused a humanitarian disaster for the

enclave's more than 2 million inhabitants.

    The Hamas attack killed 1,200 people in Israel, and led to

253 taken hostage, according to Israeli tallies.

    The White House Correspondents Association was founded in

1914 and has held a dinner nearly every year since 1921 to

celebrate the reporters who cover the presidency and raise money

for scholarships.

(Reporting by Stephanie Kelly and Jarrett Renshaw; Additional

reporting by Trevor Hunnicutt, Joey Roulette and Maria

Ponnezhath; Editing by Heather Timmons, Diane Craft, Deepa

Babington, Jamie Freed and William Mallard)

((Stephanie.Kelly@thomsonreuters.com; 646-737-4649; Reuters

Messaging: stephanie.kelly.thomsonreuters.com@reuters.net))