Speaking before the global elite in Davos, Switzerland on Tuesday, former Secretary of State John Kerry called for President Donald Trump’s resignation.

Asked what message he has for President Trump, Kerry told attendees of CNBC’s World Economic Forum panel that the president doesn’t take his position “seriously” and should “resign.”

What would John Kerry say to Trump if they were sitting across from each other? "Resign." https://t.co/jKtRgh4Vm8 pic.twitter.com/NXbMzQ5gfx — CNBC (@CNBC) January 22, 2019

Last Thursday, President Trump canceled the U.S. delegation’s scheduled trip to the annual economic conference after revoking House Speaker Nancy’s Pelosi access to military aircraft for a seven-day foreign trip, which included visits to Belgium, Egypt, and Afghanistan. “Out of consideration for the 800,000 great American workers not receiving pay and to ensure his team can assist as needed, President Trump has canceled his Delegation’s trip to the World Economic Forum in Davos, Switzerland,” White House press secretary Sarah Huckabee Sanders said in a statement at the time.

President Trump slammed the media for its coverage of his decision not to attend this year’s event — accusing them of hypocrisy for criticizing his attendance last year, while knocking him for pulling out this year. “Last time I went to Davos, the Fake News said I should not go there,” he wrote on Twitter. “This year, because of the Shutdown, I decided not to go, and the Fake News said I should be there. The fact is that the people understand the media better than the media understands them!”

Last time I went to Davos, the Fake News said I should not go there. This year, because of the Shutdown, I decided not to go, and the Fake News said I should be there. The fact is that the people understand the media better than the media understands them! — Donald J. Trump (@realDonaldTrump) January 22, 2019

Kerry, a staunch Trump critic, has repeatedly taken aim at the administration’s energy policies, calling them “profoundly dangerous” for the world. In a November interview with the Guardian, Kerry claimed “people are going to die” due to President Trump’s withdrawing the U.S. from the Paris agreement. “My kids and my grandkids are going to face a difficult world because of what Donald Trump has done,” he told the British newspaper.

Kerry has hinted at mounting another run for the presidency in recent months, telling the Harvard’s Institute of Politics that he is “not taking anything off the table.”

“But I’m not sitting around — I haven’t been running around to the most obvious states, laying any groundwork or doing anything. Am I going to think about it? Yeah, I’m going to think about it, I’ve said that point blank,” he said of a possible bid.