CNN Anchor Jake Tapper in an interview with Clinton campaign chair John Podesta. CNN CNN anchor Jake Tapper grilled Hillary Clinton's campaign chair Sunday over the FBI's announcement that it is further examining the investigation into her use of a private email server as secretary of state.

In an interview on "State of the Union," Tapper asked chair John Podesta why the campaign was criticizing FBI Director James Comey for his letter to congressional leaders. The letter informed them of new information potentially relevant to the Clinton investigation, which was reportedly found on a device Clinton aide Huma Abedin shared with estranged husband Anthony Weiner.

"You and the Clinton campaign seem to be blaming Comey for being transparent with Congress. What was he supposed to do?" Tapper asked.

Podesta reiterated his concern that Comey was unnecessarily influencing the presidential election without giving the public enough information.

"To throw this in the middle of the campaign 11 days out seemed to break with precedent and be inappropriate at this stage," Podesta said.

He added: "He might've taken the first step of actually having looked at them before he did this in the middle of a presidential campaign so close to voting."

Tapper disputed Podesta's assertion that Comey may not have even read the emails on Abedin and Weiner's computer.

"It's not that they haven't read any of them, obviously they're read some of them," Tapper said.

"Do we know that, Jake?" Podesta interjected. "Do you know that? We don't know anything."

Tapper pressed Podesta repeatedly over how Abedin's computer was overlooked by the initial investigation. He argued that the Democratic presidential nominee's top aide "hasn't been completely cooperative" with the FBI, considering she did not turn over a computer where she accessed State Department emails.

"I don't know any more than the speculation that's running wild in the press now about what this is about," Podesta said.

He added: "We don't know what computer Mr. Comey is talking about. You're assuming a lot of facts that we don't know. I think that she's been fully cooperative with the authorities. We could sit here and speculate —"

"I'm not speculating, sir," Tapper responded, pointing to CNN reports confirming that Abedin used a previously undisclosed computer that contained State Department emails.

"That's reporting, that's not speculation. You have access to Huma Abedin, I don't. Have you asked her how this happened?" Tapper asked.

"I don't think she knows anything more than what we've seen in the press to date," Podesta replied.