Attorney General Jeff Sessions will be joined by intelligence officials early Friday in a briefing on the leaks of classified information that have plagued the Trump administration.

Sessions will be joined by Director of National Intelligence Dan Coats, Deputy Attorney General Rod Rosenstein, and National Counterintelligence and Security Center Director William Evanina on Friday in Washington to discuss "leaks of classified material threatening national security," the Justice Department said Thursday afternoon.

The announcement marks the launch of a formal investigation into a series of leaks that have damaged the Trump administration since he took office in January. The Washington Post reported last week that a formal investigation was expected to be launched soon, but the Department of Justice declined to comment further on the Friday briefing.

Last week, President Trump said he wanted Sessions to do more about leaks.

"I want the attorney general to be much tougher on the leaks from intelligence agencies. These are intelligence agencies. We cannot have that happen," Trump said on Twitter hours after attacking Sessions for failing to investigate former 2016 Democratic nominee Hillary Clinton.

In May, Sessions had already said he would be cracking down on leaks.

In a statement then, Sessions said that "these leaks cannot be tolerated" and added the Justice Department had "already initiated appropriate steps to address these rampant leaks that undermine our national security."