Donald Trump names General HR McMaster as security adviser
US president Donald Trump has named Lieutenant General 'HR' McMaster as his new national security adviser.
McMaster replaces the ousted Flynn, who was forced to resign in the wake of a furore over pre-election communications with Russia.
A career army officer and strategist, McMaster is known as one of the US military's most prominent intellectuals.
Trump announced the pick at his renowned Mar-a-Lago club in Florida on Monday (US time), and said McMaster is "a man of tremendous talent and tremendous experience."
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Trump added that retired Army Lieutenant General Keith Kellogg, who had been his acting adviser, will now serve as the National Security Council chief of staff.
He also said he would be asking John Bolton, a former US ambassador to the United Nations, to work with them in a "somewhat different capacity."
Trump made the announcement from a luxurious living room, sitting on a couch between McMaster and Kellogg.
Trump brought four options for the position to Mar-a-Lago over the weekend for in-person interviews, McMaster among them.
McMaster described the appointment as a "privilege."
The president told reporters as he exited the room that Vice President Mike Pence had been involved in the process.
The position of national security adviser does not require Senate confirmation.
Trump pushed out Flynn a week ago after revelations that the adviser had misled Pence about discussing sanctions with Russia's ambassador to the US during the presidential transition.
Trump said in a news conference on Thursday (US time) that he was disappointed by how Flynn had treated Pence, but did not believe Flynn had done anything wrong by having the conversations.
Trump's first choice to replace Flynn, retired Vice Admiral Robert Harward, turned down the offer.