Sen. Ted Cruz (R-Texas) (Michael Reynolds/EPA)

Facing blowback over some the fiery rhetoric he has used in the debate over defunding the government, Sen. Ted Cruz (R-Texas) is denying that he ever referred to members of his own party as the "surrender caucus."

“I did not say that about anybody,” Cruz told radio host Laura Ingraham when asked about the use of the phrase. Asked about his chief of staff Chip Roy, who repeatedly talked about a "surrender caucus" on Twitter while sparring with Sens. John McCain (R-Ariz.) and Tom Coburn (R-Okla.) over Obamacare strategy, Cruz replied that Roy "did that on his own, and I didn't know about it, and I don't agree with that, and I have not said an ill word about any of my colleagues."

But as the Washington Examiner pointed out, Cruz himself used the phrase "surrender caucus" is a radio interview with Fox News's Sean Hannity, pronouncing himself "perpetually frustrated" by lawmakers who would give in to President Obama on everything.

"He has used that reference in general because he thinks more Republicans need to stand up and fight," spokeswoman Catherine Frazier said. "He has not singled out any of his colleagues directly," and he would not, she added.

About a dozen Republicans have committed to blocking a continuing resolution that funds the Affordable Care Act. But several of their colleagues have pushed back forcefully, arguing that the high-stakes confrontation would only cause problems for the GOP.

Since taking office in January, Cruz has been unusually free with his opinions about the Senate. In one speech at a tea party rally, he mocked some Republicans as "squishes" in the gun control debate. That kind of criticism, though directed at no specific colleague, is still rare in the Senate. Of course, critics of the defunding effort have also used some harsh language. McCain once referred to Cruz (on an unrelated issue) as one of several "wacko birds." And Coburn said they were in danger of "destroying the Republican party."