A demand that Secretary of State John Kerry testify before Congress about his department's compliance with requests for information about the Benghazi terrorist attack angered his spokesperson, who faulted lawmakers for failing to give him the opportunity to appear voluntarily.

"[I]t's highly unusual for a subpoena to be issued before there's even an official invitation for testimony. I think everyone can make their own judgments about that," State Department spokesperson Marie Harf said. "I'm not sure the secretary's even aware of the request, again, given his travel. He's scheduled to be in Mexico on the 21st, which is the date that [the House Oversight and Government Reform Committee] has asked him to testify, which HOGR would have known if they reached out to us instead of issuing a subpoena - I think by tweet, possibly," she added in an apparent allusion to committee chairman Darrell Issa, R-Calif., who tweeted throughout the day Friday the reasons for the subpoena.

"I guess that’s how they’re doing it now," Harf said tartly.

"It is because the State Dept has failed to meet its legal obligations that I have issued a subpoena to Secretary Kerry," Issa explained in one tweet.

Issa issued the subpoena -- and House Speaker John Boehner, R-Ohio, decided to form a select committee comprised of multiple House committees to investigate the Benghazi terrorist attack and its aftermath -- after the State Department produced an email showing "that top White House aides were involved in emphasizing that an anti-Islamic video provided the impetus for the 2012 attack on the U.S. compound in Benghazi," as the Washington Examiner's Susan Crabtree explained in a Thursday report. Then-U.S. Ambassador to the United Nations Susan Rice was tasked with "underscor[ing] that these protests are rooted in an Internet video, and not a broader failure of policy,” as then-White House deputy national security adviser Ben Rhodes wrote.

Harf said that is old news. "I don’t think that anybody throughout this entire process didn’t think that the communications officials at the White House responsible for our communications weren’t involved," she said. "I know Darrell Issa would like to think it is, but it’s not."

She targeted Issa again later in the conversation. "[T]he notion that there is something out there, that if Darrell Issa just keeps digging he can use politically, is just not borne out by the statistical facts of what we’ve done to look into what happened in Benghazi here," Harf said.

"I don’t know why you’re personalizing this," one of the reporters replied.

"Well, he personalized it today with the secretary," Harf said. "I think he went there first."

"All right, fair enough," the reporter replied. "But let’s – can we make a point that it is the whole committee that’s looking at it. It’s not just one guy."