Former Secretary of State John Kerry said in an interview scheduled to air Monday that President Trump’s rhetoric has given North Korea a reason to say it needs to acquire a nuclear weapon.

“I think what the president needs to do is make sure he’s not feeding into North Korea’s fear of regime change, or of you know — a unilateral attack, or otherwise,” Kerry told CNN’s Christiane Amanpour.

“And I think the rhetoric to date has frankly stepped over the line with respect to the messages that are being sent. It’s given North Korea a reason to say ‘Hey we need a bomb because if we don’t have a bomb, we’re going to — you know — not be able to protect themselves and they’ll come after us.’ ”

{mosads}Trump has sparked criticism with some of the comments he has made about North Korea and its leader. The president has on more than one occasion referred to Kim Jong Un as “Rocket Man” and in September said at the United Nations that North Korea’s leader was “on a suicide mission.”

In that same U.N. speech, Trump threatened to destroy North Korea.

“The United States has great strength and patience, but if it is forced to defend itself or its allies, we will have no choice but to totally destroy North Korea,” Trump said.

Kerry in the interview with Amanpour said the United States must engage “in the dialogue,” pushing for continued negotiations.