Former secretary of state John F. Kerry on Tuesday blasted President Trump’s tweets on the 17th anniversary of the Sept. 11, 2001, terrorist attacks, saying they reveal the president is out of touch.

In an interview with Fox News Radio, Kerry also sharply criticized Trump on North Korea and said he wishes the author of an anonymous op-ed claiming to be part of a “resistance” within the administration would have gone public and resigned in protest.

Kerry has been on a media blitz to promote his new book. He spoke hours after Trump took to Twitter on Tuesday morning to launch new attacks on the FBI and the Justice Department.

“I think about waking up on 9/11, and what did we wake up to out of the White House?” Kerry asked. “The president tweeting, attacking Jeff Sessions, his attorney general. That’s what was on his mind this morning.”

“You know, that, to me, just disturbs me — that that’s where we are — and I think it indicates being out of touch with the heart of America at the moment, at this moment and moments that really matter,” Kerry added.

Among the tweets Trump had sent out were messages commemorating the 17th anniversary of the attacks as well as broadsides against the Justice Department in which he argued, among other things, that the department should have taken stronger action against former FBI officials Peter Strzok and Lisa Page.

Trump also prompted criticism on Tuesday after a photo of him pumping his fists in the air before speaking at a memorial service in Shanksville, Pa., went viral.

On North Korea, Kerry said that Trump had failed to adequately prepare for his June summit with North Korean leader Kim Jong Un and that there is little clarity on denuclearization as a result.

“You’ve got to have a strategy, you’ve got to have more than just the glitzy meeting with the flags and so forth, and nice statements,” Kerry said.

He warned that “most long-term observers of North Korea do not believe that Kim Jong Un actually intends to give up his weapons.”

Kerry also said that while he “can’t second-guess” the decision of the author of last week’s anonymous New York Times op-ed to continue working within the administration, he wishes that person had stepped forward and resigned.

“They ought to come together and press this issue to the United States Congress because it’s serious, serious stuff,” he said.