Watch Live: National Security Adviser H.R. McMaster’s White House Press Briefing

National security adviser H.R. McMaster will hold a press conference at the White House following reports that President Donald Trump revealed classified information to senior Russian officials during an Oval Office meeting last week.

McMaster will speak to journalists, which is scheduled to start at 11:30 a.m. ET, while press secretary Sean Spicer will now hold an off-camera gaggle at 2:00 p.m. McMaster’s conference comes one day after he told the media that Trump and Russian Foreign Minister Sergei Lavrov and Russian Ambassador to the U.S. Sergey Kislyak “reviewed a range of common threats to our two countries including threats to civil aviation” but did not discuss “intelligence sources or methods.” The national security advisor added that the President did not disclose any military operations that were not already publicly known, adding: “I was in the room. It didn’t happen.”

Anonymous officials told the Washington Post that Trump shared details about an Islamic State terror threat related to the use of laptop computers on aircrafts, information provided by a U.S. partner through an intelligence-sharing arrangement. They said it was considered so sensitive that details have been withheld from allies and tightly restricted even within the U.S. government, the Associated Press reports.