Paul Ryan said Tuesday that Michael Flynn's abrupt resignation was the "right decision."
But the Republican House speaker did not give more details about the White House's knowledge of the former national security advisor's dealings with Russia before he stepped down.
"I think the president made the right decision to ask for his resignation. ... I'll leave it up to the administration to describe the circumstances," Ryan told reporters.
"As soon as they realized they were being misled by the national security advisor, they asked for his resignation."
Flynn left the post on Monday night following revelations that he misled Vice President Mike Pence and other top White House officials about his contacts with Sergey Kislyak, the Russian ambassador to the United States, before President Donald Trump's inauguration.
Reports have raised questions surrounding what White House officials knew about Flynn's conversations and when. A senior official confirmed to NBC News part of a Washington Post report that then-acting Attorney General Sally Yates told the White House last month that Flynn could be vulnerable to Russian blackmail.
In his resignation letter circulated by the White House on Monday night, Flynn did not explicitly say that he had been asked to step down.
The White House did not immediately respond to a request for comment.
Flynn told Pence he did not discuss sanctions against Russia with Russian officials in the weeks leading up to Trump's inauguration. Pence then defended him in TV interviews.
"Unfortunately, because of the fast pace of events, I inadvertently briefed the Vice President Elect and others with incomplete information regarding my phone calls with the Russian Ambassador. I have sincerely apologized to the President and the Vice President, and they have accepted my apology," Flynn wrote in his resignation letter.
Still, Democrats have called for more information on the events leading to Flynn's resignation. It comes amid wider congressional probes into the U.S. intelligence community's accusations that Russia interfered in the 2016 U.S. election.
Senate Select Committee on Intelligence Vice Chairman Mark Warner, D-Va., said Tuesday that reports about Yates' warning to the White House "raise troubling questions."
"Nothing about this resignation, or resignations that could occur in the future, precludes the Senate Intelligence Committee from continuing to investigate Gen. Flynn, or any other campaign official who may have had inappropriate or improper contacts with Russian officials prior to the election," Warner said in a statement.
House Oversight Committee Chairman Jason Chaffetz, R-Utah, suggested he may not probe the circumstances around Flynn's actions further. He told reporters "that situation is taking care of itself."