• President Donald Trump pokes fun at serious issues dogging his administration, including staff departures and the Russia investigation.

• Mocking son-in-law Jared Kushner, whose government security clearance was recently downgraded, Trump said "we're late tonight because Jared could not get through the security."

President Donald Trump delivered a few zingers about White House drama at Washington's annual Gridiron Dinner on Sunday, mocking close aides as well as the prospect of his own impeachment .

The exclusive event, organized by journalists, is essentially a roast of political figures — similar to the White House Correspondent's Dinner. Trump poked fun at grave issues currently dogging his administration, including staff departures and the ongoing Russia investigation.

Here's a summary of his top jokes.

North Korea

On North Korea , Trump said he "won't rule out direct talks with Kim Jong Un ," noting that the reclusive regime "called up a couple of days ago" and expressed a desire to talk. "As far as the risk of dealing with a madman is concerned, that's his problem, not mine," Trump said in reference to Kim.

It wasn't clear if the president was being serious. In a tweet last year, the Republican called Kim "a madman who doesn't mind starving or killing his people."

Jared Kushner

"Before I get started, I wanted to apologize for arriving a little bit late. You know, we're late tonight because Jared could not get through the security."

Trump's son-in-law had his top-level government security clearance downgraded last week , with various reports attributing the move to concern over Kushner's international business dealings .

Vice President Mike Pence

"I really am very proud to call him the apprentice. But lately, he's showing a particularly keen interest in the news these days. He starts out each morning asking everyone, 'Has he been impeached yet?' Mike, you can't be impeached when there's no crime, please remember that."

Special counsel Robert Mueller Russia inquiry has fueled calls for the president's impeachment, but Trump denies claims of collusion with the Kremlin.

Jeff Sessions

"I offered him a ride over, and he recused himself. What are you gonna do? But that's OK."

The attorney general removed himself from the Russia investigation last year, citing potential conflicts of interests, in a move that sparked Trump's ire .

White House resignations

"So many people have been leaving the White House. It's invigorating since you want turnover. I like chaos. It really is good. Who's going to be the next to leave? [Adviser] Steve Miller or [first lady] Melania Trump ?"