In a letter to President Donald Trump, Rosenstein said he would depart on May 11, after more than two turbulent years as the number two official in the Department of Justice.

The veteran Republican prosecutor, 54, stunned the country on May 17, 2017 when he named an independent lawyer to take on the Russia probe after Trump fired FBI director James Comey.

Then-attorney general Jeff Sessions had already recused himself from overseeing the investigation, leaving Rosenstein in charge.

That made Rosenstein effectively the one buffer between Mueller and the White House – a position that became even more crucial when the investigation began examining whether Trump himself had obstructed justice by firing Comey and then trying to have Mueller fired.

In his final report released on April 18, Mueller concluded that no one on Trump’s campaign conspired to collude with Russians.

But he reached no conclusion on obstruction, detailing the evidence he had accumulated and leaving it to Congress to act.

Rosenstein had made clear last year that he would step down after Mueller’s report was released.

In his resignation letter, he said the Justice Department had made “rapid progress” in reducing crime, protecting consumers, and enforcing immigration laws during his tenure.