( CNN) Defense attorney and constitutional law scholar Alan Dershowitz mentioned Monday that President Donald Trump is now facing “the most serious accuse ever made against a sitting president” after reports that he shared highly classified information with Russia’s foreign minister and diplomat during a White House visit last week.

“I get great intel. I have people brief me on great intel every day, ” one official with knowledge told the Post Trump mentioned, before the President reportedly relayed specific classified intelligence.

Multiple administration officials denied the tale, including national security adviser H.R. McMaster, who mentioned, “I was in the chamber, it didn’t happen” and “at no time were intelligence sources or methods discussed and the President did not disclose any military operations that weren’t already publicly known.”