Washington — President Biden joked about former President Donald Trump during remarks at the Gridiron Club Dinner in Washington, D.C. late Saturday, turning criticism about his age on the former president as the general election gets underway. But he also took the opportunity to address the more serious — warning of threats to freedom and democracy in the U.S. and abroad. 

Speaking to hundreds of journalists and leaders at his first appearance at the annual dinner, Mr. Biden said the two candidates had clinched their party's nomination this week for president, saying that "one candidate is too old, mentally unfit to be president."

"The other's me," he quipped. 

The president went on to take aim at his political rival, joking about Trump's references to running against former President Barack Obama in 2024. He also alluded to an incident where Trump appeared to refer to his wife by the wrong name. 

"And another big difference between us — I know what I value most," Mr. Biden said. "I'm Jill Biden's husband. And I know her name." 

But the remarks also veered toward the serious, as the president cited threats to democracy and freedom. 

Highlighting what his administration has accomplished over the last few years, the president said the work was done "all without destroying the economy, embarrassing us around the world or itching for insurrection," in an apparent nod to Trump.

"Look, I wish these were jokes but they're not," he continued. 

Mr. Biden warned that "we live in an unprecedented moment in democracy" when "democracy and freedom are really under attack." He cited Russian President Vladimir Putin's "march on Europe," while noting that Trump encouraged Putin to "do whatever the hell you want" with NATO allies that don't spend enough on defense. 

The president urged that at home, freedom is "under assault," making reference to voting rights and abortion. He warned that the threat apparent during the effort to overturn the 2020 election remains, calling it "poison" within the "veins of our democracy."

Remarks at last year's dinner took a similarly serious tone, when former Vice President Mike Pence delivered what was at the time among his strongest rebukes of the former president, saying that "history will hold Donald Trump accountable" for his election denialism. 

Also speaking at this year's event was Utah Gov. Spencer Cox and Michigan Gov. Gretchen Whitmer. 

Fin Gomez contributed reporting.

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• Joe Biden
• Donald Trump

Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.

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