Rosenstein, who was nominated to his current post in Maryland by President George W. Bush in 2005, will be heading the No. 2 spot at the Justice Department, The Wall Street Journal quoted a person familiar with the matter as saying.

The Attorney is a well-liked, longtime official who has worked for both Republicans and Democrats in charge of any pending investigation into Hillary Clinton.

Trump's pick for Attorney General, Senator Jeff Sessions, on Tuesday said he would recuse himself on any Clinton-related matters, given his statements critical of her on the campaign trail.

That would leave the Deputy Attorney General in charge of decisions related to the Democrat, if there are any.

A federal probe into Clinton's use of a private email server while she was the Secretary of State was closed last year without any charges being filed, though James Comey, the head of the FBI, has said the agency would consider any new information that surfaced.

Within the Federal Bureau of Investigation, some agents also have spent more than a year probing the financial relationships of the Clinton Foundation charity, to see if donations were tied to influence-peddling while she was Secretary of State.

Justice Department officials rebuffed their efforts to expand that investigation, saying their findings to date did not merit it.

Rosenstein has handled a multitude of investigations involving classified information, in large part because the National Security Agency is based in his jurisdiction.

Rosenstein first joined the Justice Department in 1990 and prosecuted public corruption cases. He served as a counsel to the Deputy Attorney General, among other positions, during the Clinton and Bush administrations.

He was unanimously confirmed by the Senate in 2005 to be the Maryland's US Attorney, or chief federal prosecutor. He would need to be confirmed by the Senate for his new post.