National Security Adviser H.R. McMaster on Tuesday reiterated that President Donald Trump did nothing wrong in sharing sensitive information about the Islamic State terrorist organization with a pair of Russian diplomats.

McMaster fielded questions from reporters for the first time since The Washington Post reported Monday that Trump shared classified information in a White House meeting with Russian Ambassador Sergey Kislyak and Foreign Minister Sergey Lavrov.

“What I’m saying is, really the premise of that story was false, that any way the president had a conversation that was inappropriate or that resulted in any kind of lapse in national security.”

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“I stand by my statement that I made yesterday,” he said at the White House press briefing. “What I’m saying is, really the premise of that story was false, that any way the president had a conversation that was inappropriate or that resulted in any kind of lapse in national security.”

McMaster said what has endangered national security is leaks of classified information to the news media.

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“Our national security has been put at risk by those violating confidentiality, and those releasing information to the press that could be used, connected with other information available, that could make American citizens and others more vulnerable,” he said.

Fred Fleitz, a former U.S. intelligence official who now is senior vice president for policy and programs at the Washington-based Center for Security Policy, noted that the president has ultimate authority to classify or declassify information as he sees fit. He blasted current and former officials who took it upon themselves to second-guess the president’s decision and undercut him through The Washington Post.

“In doing so, they leaked a substantial number of highly classified details to The Washington Post,” he told LifeZette. “This is a very serious crime. We can argue about whether Trump made a mistake. But we know what they did was highly illegal.”

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Fleitz criticized “people who took it upon themselves to determine what is appropriate or not. And they should go to jail.”

The Post story quoted current and former national security officials. That suggests that former senior officials from the administration of former President Barack Obama learned information from current staffers and then told reporters, Fleitz said.

“That is inappropriate,” he added.

Fleitz, whose career included stints with the CIA, the Defense Intelligence Agency, and the State Department, said he witnessed that phenomenon when he worked in the George W. Bush administration. National security officials would call their old bosses from the Bill Clinton administration and consult with them on current intelligence issues, he said.

One of the biggest concerns raised by The Post and Trump’s critics is that the information Trump shared with the Russians came from an allied country that did not authorize its dissemination. The concern is that the incident will discourage cooperation on intelligence issues by foreign governments.

Said Fleitz: “They’re already not sharing information with us because of all the leaks in the Obama administration.”

He pointed to newspaper accounts that included key details of the raid that killed master terrorist Osama bin Laden and the existence of Stuxnet, a computer virus deployed to sabotage Iran’s nuclear program.

Fleitz also pointed to a statement at a Senate Judiciary Committee hearing earlier this year by Sen. Dianne Feinstein (D-Calif.) in which she revealed classified information that the government paid $900,000 to break into a locked iPhone used by the gunman in the San Bernardino, California, terrorist attacks in 2015.

Democrats kept up a steady drumbeat against Trump on Tuesday. Sen. Chris Murphy (D-Conn.) ridiculed Trump’s “foreign policy by improvisation” during an event at the left-wing Center for American Progress. He said sharing classified information is appropriate if it is part of a formal, strategic process.

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“This clearly, as far as we know, was not strategic,” he said.

Rep. Adam Schiff (D-Calif.), the ranking Democrat on the House Intelligence Committee, said at the same event that the story fits with a troubling pattern of Trump’s actions as president.

“They all have an improvisational character,” he said. “Some have an erratic character.”

Rep. Mo Brooks (R-Ala.), a member of the House Armed Services and Foreign Relations committees, told LifeZette that it is premature to make definitive statements.

“Right now, we do not have enough information to make an informed decision,” he said. “Right now, we have the rumor mill.”