In a subtle jibe at Donald Trump, President Joe Biden on Tuesday cracked a joke while talking about his long relationship with Chinese President Xi Jinping.

What Happened: The incumbent president recalling his ties with Xi, which goes back more than a decade to when they were both vice presidents, said, "I've allegedly met more face-to-face with Xi Jinping than any world leader has."

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"I had a lot of personal, just one-on-one conversations. And we each had a simultaneous interpreter," Biden said at a meeting in a roomful of diplomats at an event honoring the U.S. State Department's Chiefs of Mission.

He then cracked: "I turned all my notes in," in witting reference to Trump, who on Tuesday was arraigned on 37 federal counts relating to classified documents he refused to return to upon leaving the White House. 

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Biden's joke garnered a huge laugh from the audience. 

"And that's not a reference to the president, the former president," Biden said before he drew some more laughs.

"But look, no, it really isn't."

See Also: Trump Faces ‘Fight Of His Life,’ Says Ex-Federal Prosecutor: ‘Consequences Are Going To Be Much More Severe’ 

Why It Matters: Earlier in the day, Trump made his first court appearance after being indicted in the classified document case last week. Trump pleaded not guilty to the federal charges and has continued to maintain his innocence. 

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