United States President Donald Trump on Wednesday named his chief hostage negotiator Robert O'Brien as the new National Security Adviser to replace John Bolton, who was fired last week.
O'Brien, who has been serving as the special envoy for hostage affairs at the Department of State, has been chosen for the role, Trump tweeted.
'I am pleased to announce that I will name Robert C. O'Brien, currently serving as the very successful Special Presidential Envoy for Hostage Affairs at the State Department, as our new National Security Advisor.
'I have worked long & hard with Robert. He will do a great job!' he said.
In his role as special presidential envoy for hostage affairs, O'Brien works with families of American hostages and advises on related issues, including recovery policies.
In choosing O'Brien to replace Bolton, the president tapped a longtime lawyer who has impressed him with his work to extricate Americans detained by countries like North Korea and Turkey, The New York Times reported.
O'Brien would be Trump's fourth national security adviser of his presidency.
On Tuesday, the White House said President Trump has shortlisted five people for the NSA'S position.
The five names are of Robert O'Brien, Ric Waddell, Lisa Gordon-Hagerty, Fred Fleitz and Keith Kellogg, the White House said.
Trump fired his hawkish National Security Advisor Bolton on September 11, saying he 'disagreed strongly' with many of his suggestions.
The president defended his decision to fire Bolton, saying the latter had done some 'big mistakes' and his actions were not in line with the administration.
Appointed in April 2018, Bolton was the third national security adviser to leave the White House, after Michael Flynn and H R McMaster.
O'Brien has previously served under the George W Bush and Barack Obama administrations.
The role does not require confirmation by Congress.
O'Brien served as a major in the US Army Reserve.
Former President Bush appointed him in 2005 to serve as a representative to the United Nations general assembly.
While at the UN, he worked with Bolton, who was then the ambassador.