In late October, Petraeus traveled to Libya to conduct his own review of the Benghazi attack that killed four Americans, including U.S. Ambassador Christopher Stevens.
While in Tripoli, he personally questioned the CIA station chief and other CIA personnel who were in Benghazi on Sept. 11 when the attack occurred.
The Libya stop was part of a six nation trip to the region. Petraeus intended the review as a way to prepare for his upcoming testimony before Congress on Benghazi.
"He was looking forward to testifying," a Petraeus friend told ABC News. "He wanted to be fully prepared."
Petraeus' friend described his investigation as Petraeus' "personal review" of both the Sept. 11 attack and the events leading up to it.
The trip was so recent that the CIA has told the Congressional Intelligence committees that the trip report has not yet been completed.
Petraeus' personal involvement in this investigation is one reason some in Congress are likely to insist he testify on Benghazi.
But now Petraeus is telling friends he does not think he should testify.
Petraeus has offered two reasons for wanting to avoid testifying: Acting CIA Director Morell is in possession of all the information Petraeus gathered in conducting his review and he has more current information gathered since Petraeus' departure; and it would be a media circus.