(ABC NEWS) -- Donald Trump's national security adviser, H.R. McMaster, said today the president did not know where the information he shared with Russian officials had originated and described the conversation as "wholly appropriate."

"The president wasn't even aware where this information came from. He wasn't briefed on the source or method of the information either," McMaster said at a press briefing.

The Washington Post reported Monday that Trump had disclosed classified information in a meeting with Russian officials last week. McMaster initially called the story "false," but today described the premise of the story as "false."

"What was shared was wholly appropriate given the purpose of that conversation and the purpose of what the president was trying to achieve through that meeting," McMaster said.

When pressed by ABC News' Jonathan Karl, McMaster would not say if Trump had disclosed classified information. Trump said in a pair of tweets Tuesday he had the "absolute right" to share "facts" with the Russians.

"We don't say what's classified, what's not classified. What I will tell you again is that what the president shared was wholly appropriate," he said.

On Monday, McMaster said "at no time were intelligence sources or methods discussed. And the president did not disclose any military operations that were not already publicly known."

McMaster said he was in the room for the May 10 meeting in the Oval Office, noting that the larger conversation was "about the terrorist threat."

"The president was emphasizing we have some common interests here. We have to work together in critical areas," McMaster said.

"So this was the context of the conversation in which it was wholly appropriate to share what the threat was as a basis for common action and coordination," he said.