(This story corrects year to 2001 in paragraph 17 in the February 18 story.)

U.S. President Donald Trump holds a "Make America Great Again" rally at Orlando Melbourne International Airport in Melbourne, Florida, U.S. February 18, 2017. REUTERS/Kevin Lamarque

MELBOURNE, Fla. (Reuters) - President Donald Trump will interview four candidates for the position of U.S. national security adviser on Sunday and expects to make a decision in the coming days, he told reporters on Saturday.

Trump will interview acting adviser Keith Kellogg, former U.S. ambassador to the United Nations John Bolton, Lieutenant General H.R. McMaster and Lieutenant General Robert Caslen, White House spokesman Sean Spicer told reporters at Trump’s Mar-a-Lago resort in Florida.

“I’ll make a decision over the next couple of days,” Trump told reporters later on Air Force One. He said he was leaning toward one of the candidates he was interviewing on Sunday.

Trump, who has been searching for a new national security adviser after firing his first one, Michael Flynn, could add a couple more candidates to the list, Spicer said.

Retired general and former CIA chief David Petraeus is no longer a candidate. The retired four-star general, who resigned as head of the CIA in 2012 after it was revealed he was having an affair with his biographer, had been on a short list for the job after Flynn was let go.

Spicer said Trump’s finalists include Kellogg, Bolton, Caslen, who is the superintendent of the U.S. Military Academy at West Point, and McMaster, who holds a senior post with the U.S. Army Training and Doctrine Command.

Former U.S. National Security Agency head Keith Alexander, and former Army chief of staff Ray Odierno were also thought to be in contention for the job.

Flynn stepped down early this week after revelations that he had discussed U.S. sanctions on Russia with the Russian ambassador to the United States before Trump took office and misled Vice President Mike Pence about the conversations.

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Finding a replacement has been a challenge for Trump. Retired Vice Admiral Robert Harward, the president’s first choice to take over for Flynn, turned down the offer, citing family and financial reasons.

A source familiar with the matter said Petraeus, like Harward, wanted control over staffing decisions within the NSC, and Trump was reluctant to grant that authority.

Trump is spending the weekend at his properties in Florida.

“Will be having many meetings this weekend at The Southern White House,” he wrote in a tweet on Saturday morning.

The president spent the morning at the Trump International Golf Club before returning to his Mar-a-Lago resort. He later held a political rally in Melbourne, Florida.

The tumult in Trump’s security team stretched into other areas of the National Security Council, the president’s main forum for decision-making on security and foreign affairs.

The White House dismissed Craig Deare, the NSC’s senior director for Western Hemisphere Affairs, after receiving reports that he had criticized the president and top aides, Politico reported. An NSC spokesman declined to comment.

McMaster is a highly regarded tactician and strategic thinker with a PhD, who as a captain in 1991 commanded a small troop of the U.S. 2nd Armored Cavalry Regiment that destroyed a much larger Iraqi Republican Guard force at a place called 73 Easting, for its map coordinates, in what many consider the biggest tank battle since World War II.

Caslen, a West Point graduate, was serving in the Pentagon on September 11, 2001, and joined others after the attack in rushing into the damaged part of the building to search for survivors. He served in the Gulf War, Afghanistan, and Iraq.

The Pentagon Inspector General found that he and other generals violated Defense Department ethical guidelines by appearing in a video promoting Christian Embassy, a non-profit evangelical group previously known as the Campus Crusade for Christ.