The White House has broken its silence on the future of Michael Flynn as a senior adviser said Donald Trump retains "full confidence" in his national security adviser after reports that he misled senior officials about contacts with Russia.
Mr Flynn had apologised privately for the controversy to vice president Mike Pence, according to an administration official.
Mr Pence, relying on information from Mr Flynn, publicly vouched that the retired army lieutenant general did not discuss sanctions with Russia's ambassador to the US, Sergey Kislyak.
Mr Flynn has since told the White House that sanctions might have come up in the calls.
Mr Trump has still said nothing about Mr Flynn following a Washington Post report last week confirming that sanctions were a topic of conversation, but White House aide Kellyanne Conway said: "He has the full confidence of the president."
Mr Flynn sat in the front row of Mr Trump's news conference earlier on Monday with Canadian prime minister Justin Trudeau, but the president did not heed a question about Mr Flynn's future from a pair of reporters and he ignored journalists' shouted follow-up inquiries as he left the room.
Mr Trump told associates over the weekend that he was troubled by the situation, but did not indicate that he planned to ask Mr Flynn to step down, according to a source.
Mr Flynn was a loyal Trump supporter during the election campaign, but he is viewed sceptically by some in the administration's national security circles, in part because of his ties to Russia.