Susan Rice's abrupt withdrawal from consideration for secretary of state, coupled with suggestions from the State Department that Secretary Hillary Clinton may not testify as scheduled next week, has stirred speculation that something big is brewing in the Libya terror attack investigation.

"You're starting to see the State Department squirm a little bit," Rep. Jason Chaffetz, R-Utah, said.

For the better part of the last three months, an independent board has been conducting a review for the State Department of the Sept. 11 terror attack in Benghazi. In anticipation of the report's conclusion, two congressional committees scheduled hearings for next week in which Clinton was set to testify.

State Department spokeswoman Victoria Nuland, though, surprised lawmakers and reporters on Thursday when she indicated the report, and the secretary, might not be ready.

"The Hill has talked about a planning date on the calendar. That presumes that the (report) is finished," Nuland said. "I don't have any dates, any schedule of the secretary's to announce here."

Asked whether Clinton has committed to testify, Nuland said "it's dependent on the work being finished."

Further, Nuland rejected the notion that the final report on Libya needed to be shared with Congress at all. She stressed, instead, that the only thing the statute requires is for "the secretary's response" to the report's conclusion to be sent to Congress.

The comments were met with surprise on Capitol Hill. A spokesman for House Foreign Affairs Committee Chairwoman Ileana Ros-Lehtinen, R-Fla., who scheduled a hearing for Dec. 20, said this was the first they heard a scheduling issue.

Senate Foreign Relations Committee Chairman John Kerry, D-Mass., said it's still "the plan" for Clinton to testify on his committee next week.

But Fox News is told that Rep. Mike Rogers, chairman of the House intelligence committee, believes there was gross negligence on behalf of the State Department for not providing adequate security to Ambassador Chris Stevens.

Chaffetz told Fox News that if done accurately, the final report will be a "very difficult thing" for the State Department, the CIA, the Department of Defense and the White House to explain.

Chaffetz also speculated that Rice's announcement Thursday that she's withdrawing from consideration for secretary of state is related.

"The State Department owes us a report," he told Fox News. "That's why I think Susan Rice made the announcement today, because I think we're on the verge of getting that report."

Nuland insisted Thursday that, whatever the timeframe, Clinton will be "transparent and open with Congress."

She said Washington needs to wait for the report to be completed, "and we'll go from there."

For her part, Rice said she was withdrawing because she did not want to subject the Obama administration to a "lengthy, disruptive and costly" confirmation process.

Many Republicans were opposed to the possibility of her nomination over concerns about her Sept. 16 comments in which she described the Libya attack as tied to a "spontaneous" demonstration. They questioned why she was chosen by the administration in the first place to do a round of Sunday show interviews.

Rice, though, tried to explain as she bowed out of the running Thursday. In an interview on NBC News, she said Clinton was originally asked to go on the networks, but "she had had an incredibly grueling week dealing with the protests around the Middle East and North Africa," as well as the deaths of department employees, and declined. So Rice stepped in.

In a Washington Post column, Rice said her comments were based on intelligence at the time. "It would have been irresponsible for me to substitute any personal judgment for our government's and wrong to reveal classified material," she wrote.