President Donald Trump is expected to nominate John J. Sullivan to be the deputy secretary of state, the Wall Street Journal reported, citing anonymous U.S. officials familiar with the development.

Sullivan, who has previously served in the George W. Bush administration at senior positions in the Commerce Department and the Pentagon, was announced as Trump administration’s pick to be the Pentagon’s general counsel, earlier this month. However, officials privy to the situation said that the 57-year-old would instead be roped in as Rex Tillerson’s second in command after Tillerson himself made the recommendation.

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Tillerson reportedly met Sullivan before his confirmation hearing and the latter role-played as a senator to help Tillerson prepare. The two have kept in touch since. Tillerson also reportedly approached Defense Secretary Jim Mattis on the sidelines of the Washington conference of 68 members of the international coalition to defeat the Islamic State.

“Mattis was totally ok with him being poached,” the anonymous officials familiar with the matter, reportedly told WSJ.

Tillerson has been the subject of criticism recently as he has been slow in appointing officials at the deputy secretary, assistant secretary and undersecretary level. It was also recently reported that more than 100 management posts and foreign ambassadorships are also awaiting nomination, according to Washington Times. Only three ambassadors for China, Israel and Britain, have been named.

Tillerson was also criticized for snubbing the Washington Press corps during his recent trip and also for not engaging with reporters by postponing press briefings.  It was also recently reported that Tillerson did not want the job as secretary of State and later accepted it after his wife advised him to do so.

Even though Sullivan’s nomination hasn’t been confirmed, he received a stellar nomination from Arnold Punaro, a former staff director for the Senate Armed Services Committee.

“If this is true, we should not consider this to be a loss for the Pentagon, but a huge gain for our overall national security establishment,” Punaro said.