Rep. Peter King (R-NY) criticized the FBI's handling of the investigation of the extramarital affair that resulted in CIA Director David Petraeus' resignation.

"To have someone out there in such a sensitive position who the FBI thought perhaps could have been compromised or was under the scope of an FBI investigation who may or may not have been having an affair at the time, that, to me had to have been brought to the president, certainly to the National Security Council," King told MSNBC host Joe Scarborough Monday. "If not, the FBI was derelict in its duty."

Petraeus, who has been married for 38 years, cited the affair as the reason for his resignation Friday in a memo to CIA staff, saying, "such behavior is unacceptable, both as a husband and as the leader of an organization such as ours." The other woman was later identified as Paula Broadwell, who co-wrote a biography on Petraeus.

Petraeus' resignation came less than a week before he was scheduled to testify before the House and Senate intelligence committees on the Sept. 11 attack that killed four Americans at a U.S. consulate in Benghazi, Libya. Sen. Saxby Chambliss (R-GA), who serves on the Senate Select Committee, said Sunday he was "confident" Petraeus would still be called upon.

The Associated Press reported Monday that officials first learned about the affair while investigating threatening emails Broadwell allegedly sent to Jill Kelley, a family friend of Petraeus' and an "unpaid social liaison" working at MacDill Air Force Base in Tampa, Florida; one official said emails in Broadwell's account contained information confirming the affair with Petraeus.

The New York Times reported Monday that FBI and Justice Department officials were notified about the investigation into the affair as far back as last summer, but did not push the issue further up the chain of command in part because worries over possible security breaches "did not appear to be justified."

According to CNN, however, at least one FBI employee told Rep. Dave Reichert (R-WA) and House majority leader Rep. Eric Cantor (R-VA) about the probe last month. Cantor reported his encounter with the employee to the bureau on Oct. 31.

King said Monday that Attorney General Eric Holder and FBI Director Robert Mueller should have gone to President Barack Obama as soon as they were alerted to the investigation into Petraeus' correspondence with Broadwell because Obama, as Commander-in-Chief, needs to be able to trust his foreign policy team.

"This is a crisis, I believe, of major proportions," King said. "This is not your usual political thing -- we're not talking about a Secretary of Commerce or some undersecretary somewhere."

Watch King discuss the Petraeus investigation, as aired on MSNBC Monday, below.

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