House Budget Chairman Paul D. Ryan, R-Wis., is choosing his words carefully when discussing the tenuous relationship between GOP lawmakers and conservative outside groups.

In sneak-peek excerpts from an interview to be aired on NBC’s “Meet the Press” this Sunday,  Ryan — who sat for questions with host David Gregory alongside Senate Budget Chairwoman Patty Murray, D-Wash. — conceded that he was “frustrated” with outside advocacy groups, such as Heritage Action for America and Americans for Prosperity, which “came out in opposition to our budget agreement before we reached a budget agreement.”

But Ryan was quick with a caveat, adding, “I think these taxpayer groups are indispensable to keeping taxpayer interest accounted for, keeping people accountable.

“We sometimes have difference of opinions on tactics,” Ryan continued. “We all believe the same thing with respect to our ultimate goal.”

Simmering tensions between Heritage Action, Americans for Prosperity and the like came to a boil this week, when Speaker John A. Boehner, R-Ohio, devoted portions of two consecutive news conferences to slamming their strong-arm tactics intended to kill certain leadership-backed legislation.  In harsh tones, he accused them of “using” and “misleading” members of the House Republican Conference, and said the groups had “lost all credibility.”

In the excerpts made public on Friday, Ryan appeared to downplay the extent of Boehner’s anger.

“Well, look. I think John just kind of got his Irish up,” Ryan said. “He was frustrated that these groups came out in opposition to our budget agreement before we reached a budget agreement. I was frustrated, too. But I think these are very important elements of our conservative family. I would prefer to keep those conversations within the family. And I think he was just basically voicing his frustration with their opposition before we had reached an agreement.”