“One thing I won’t do is just say as a candidate: ‘I’m just going to tear up the agreement on the first day.’ That sounds great, but maybe you ought to check in with your allies first,” Bush told reporters in Carson City, Nevada, on Friday.

He said a secretary of state and a secretary of defense should be put in place first. “You might want to have your team in place before you take an act like that,” said Bush.

Such talk prompted a rare response from the Walker team to Bush, a possible prelude to a clash over the issue when the candidates have their first debate on Aug. 6 in Cleveland.

The Walker campaign blasted out a statement from foreign policy adviser Robert C. O’Brien that rejected Bush’s view without mentioning him by name.

“We don’t need more information, we don’t need to wait to confirm the next Secretary of State, we need decisive leadership and we need it now. This won’t be easy, but when America leads, and has a strong president with clear priorities who believes in American strength, the rest of the world will follow,” O’Brien said.