Harward, Petraeus under consideration to replace Flynn as national security adviser

— -- In the immediate aftermath of national security adviser Michael Flynn’s resignation, ABC News has learned that retired Navy Vice Adm. Robert Harward and former CIA Director David Petraeus are two of the potential candidates to replace him.

Flynn resigned in the wake of allegations that he spoke about United States sanctions against Russia with the Russian ambassador to the U.S. before the inauguration of President Donald Trump and then misled the administration about the discussions.

Harward formerly served as the deputy commander of U.S. Central Command (CENTCOM). A 38-year member of the Navy, Haward was the commander of a SEAL team and led troops in Afghanistan and Iraq before working on the National Security Council under President George W. Bush, according to his official Navy biography. Harward is an ABC News contributor.

With CENTCOM, Harward reported to current Secretary of Defense James Mattis, who was then CENTCOM commander.

Petraeus, a retired four star Army general who served as CIA director from 2011-2012, under President Barack Obama, was previously the commander of the International Security Assistance Force in Afghanistan and of CENTCOM. Petraeus served 37 years in the Army before retiring and taking the CIA job.

His resignation from that position in the midst of an affair with his biographer made headlines when it was revealed that he provided her with classified information. Petraeus later plead guilty to a misdemeanor charge for the offense.

During the presidential transition, Trump considered Petraeus for the position of secretary of state, which ultimately went to former ExxonMobil CEO Rex Tillerson.

Until a permanent decision is reached, the White House announced Monday night that retired Army Lt. Gen. Keith Kellogg will serve as acting national security adviser.

ABC News’ Jonathan Karl contributed to this report.