President Trump will soon announce that Deputy Secretary of State John Sullivan will be the next U.S. ambassador to Russia, a senior administration official confirmed to Fox News Friday.

Sullivan will replace Jon Huntsman, who left the post last week. Fox News reported in August that Trump intended to nominate Sullivan. The Wall Street Journal first reported Friday that Moscow agreed to accredit Sullivan -- a precursor to a formal nomination.

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Sullivan, a lawyer with a long history of federal service, has been deputy secretary of state since May 2017 when the Senate confirmed him 94-6. He briefly led the State Department in the period between former Secretary of State Rex Tillerson’s dismissal in March 2018 and Mike Pompeo’s swearing-in the following month.

Sullivan’s career in government dates back to 1991, when he served as counselor to Assistant Attorney General J. Michael Luttig in the Justice Department’s Office of Legal Counsel. During the administration of President George W. Bush, Sullivan served as deputy general counsel to the State Department before moving on to the role of general counsel at the Department of Commerce.

The Journal reports that he is currently leading a pair of ongoing dialogues with Russia relating to counterterrorism and strategic security. Sources told the outlet that Sullivan played an important role in the expulsion of Russia diplomats after the poisoning of a former double agent and his daughter in England in 2018.

Fox News’ Andrew O’Reilly contributed to this report.