U.S. President Donald Trump on Tuesday listed five possible replacements for recently fired national security adviser John Bolton, most of whom are already familiar faces from within his administration, reports Trend referring to Reuters.

The national security adviser provides advice to the president on defense, security and diplomatic issues. The job, the highest White House position on national security, does not require confirmation by the U.S. Senate.

The candidates Trump said he was considering include Ricky Waddell, who was deputy national security adviser for a year when retired General H.R. McMaster had the top job, and Vice President Mike Pence’s security aide Keith Kellogg, who was executive secretary of the National Security Council until Bolton took over the office 17 months ago.

A third candidate is hostage negotiator Robert O’Brien, who has a long history in Republican foreign policy circles.

Speaking to reporters aboard Air Force One, Trump said another possible successor to Bolton was Fred Fleitz. A former CIA officer, Fleitz has also served as executive secretary of the National Security Council and was Bolton’s chief of staff at the State Department.

An outspoken critic of Iran, Fleitz has espoused hard-line views on Islam. He told Breitbart News in 2017 that some Muslim communities in the United States were susceptible to a "radical world view that wants to destroy modern society, create a global caliphate, and impose sharia law on everyone on Earth.”

Trump’s fifth listed candidate is Lisa Gordon-Hagerty, under secretary for nuclear security of the U.S. Department of Energy.

Gordon-Hagerty has worked in the private sector and as a staff member in the U.S. House of Representatives on security issues. She also served on the National Security Council and in other roles in the Energy Department addressing crisis management, emergency response and nuclear weapons.

However, White House spokeswoman Stephanie Grisham issued a statement later saying the list mentioned by Trump to the reporters "was not the full list, and there are others being considered.” She did not name any additional people.

Bolton was abruptly fired last week over his handling of North Korea and Venezuela. A leading foreign policy hawk and Trump’s third national security adviser, Bolton had pressed the president not to let up pressure on North Korea despite diplomatic efforts.