Rep. Trey Gowdy said Sunday he'll summon Secretary of State John Kerry before his select committee investigating the 2012 Benghazi attacks if he doesn't get the documents his panel is seeking.

The South Carolina Republican accused the State Department of holding back not only on a complete release of emails from former Secretary of State Hillary Clinton, but also those of nine of her 10 closest aides, for more than a year.

"I'm trying to do this the right way," Gowdy told CBS. "I'm trying to do this without the drama, just the documents. But that has not proven to be successful."

"I want to get this investigation over with and [Kerry] is the only thing standing between me and a completed investigation," said Gowdy.

Gowdy said Clinton will be called to testify "just as soon as the Department of State decides to give me the documents that I need to have a constructive conversation with her."

Renewed scrutiny of Clinton's private email use bubbled up last week after it became clear that Sidney Blumenthal, an unofficial adviser to Clinton, had given Congress 60 emails that the State Department never provided.

The department admitted Thursday it could not locate all or part of 15 of those messages, and spokesman John Kirby said Friday that the department had no plans to launch a probe of Clinton's private server, which hosted both personal and work-related emails.

"Secretary Kerry has made it clear he wants us to cooperate with the committee to the fullest extent and to be as helpful as we can," Kirby said. "That said — and we've made this clear — the more that's being asked for with respect to that — to their task, the longer it's going to take, the more resources are going to have to be applied when it goes well beyond what the original mandate was."

Gowdy hit back at criticism that the Benghazi investigation had dragged on too long, saying the discovery that State had no record of the 15 emails was proof the public record is not complete and Clinton's explanations are "demonstrably false."

"I am happy to conclude this investigation just as soon as John Kerry decides that he's going to give us the documents that we're entitled to," said Gowdy.