(Bloomberg) -- President-elect Joe Biden intends to name his longtime adviser Antony Blinken as secretary of State, according to three people familiar with the matter, setting out to assemble his cabinet even before Donald Trump concedes defeat.

In addition, Jake Sullivan, formerly one of Hillary Clinton’s closest aides, is likely to be named Biden’s national security adviser, according to two people familiar with the matter. An announcement is expected Tuesday, the people said.

Biden’s incoming White House chief of staff Ron Klain said Sunday the president-elect would be making his initial cabinet announcements on Tuesday, but he declined to specify which positions would be filled first. The people familiar with Biden’s selections asked not to be identified because he hasn’t yet made the announcements.

Both Sullivan, who is 43, and Blinken, 58, served stints as Biden’s national security adviser when he was vice president.

State is regarded as one of the most prestigious cabinet posts. The secretary of State is the nation’s top diplomat, conducting meetings with foreign leaders across the globe.

The president’s national security adviser is one of the most important and powerful jobs in the White House, leading a staff of dozens of experts drawn from the government’s military, diplomatic and intelligence agencies who develop U.S. foreign and military policy.

Blinken and Sullivan did not immediately respond to requests for comment. A Biden spokesman declined to comment.

Blinken has been regarded as one of the leading candidates to run the State Department. After serving as the vice president’s national security adviser, he was elevated to deputy secretary of state under President Barack Obama.

When Biden was a senator, Blinken served as his staff director on the Senate Foreign Relations Committee before leaving to work on Biden’s 2008 presidential campaign.

Following the Obama administration, Blinken co-founded WestExec Advisors, a political strategy firm, with a top Obama-era Pentagon official, Michele Flournoy.

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