Former Vice President Dick Cheney told members of House Republican leadership Tuesday to be wary of North Korean leader Kim Jong Un in the escalating situation in the Korean Peninsula.

Cheney attended a leadership meeting in the office of Speaker John A. Boehner of Ohio before walking to the office of Majority Whip Kevin McCarthy of California to speak with the GOP whip team. He came at the behest of McCarthy, according to aides and members.

Cheney declined to say what he told the members, saying it was a private meeting. “I’m concerned about it, of course, like I’m sure everyone is,” he said.

Rep. Steve Southerland II, R-Fla., said Cheney warned members not to underestimate the 26-year-old North Korean leader.

“He could have a lot of things up his sleeve, not just military power,” Southerland said. Cheney “emphasized the fact that this is a guy you cannot underestimate . . . because we don’t know anything about him. Our intel on him is sketchy at best. He’s young, so he doesn’t have a track record, and don’t eliminate any possibility of what his intentions are: blackmail, actual use of force or using it as a [bargaining] chip.