WASHINGTON - US President-elect Donald Trump on Wednesday picked his ex-aide Peter Navarro to serve as senior counselor for trade and manufacturing in his next administration, and former commissioner of the US Securities and Exchange Commission (SEC) Paul Atkins to be the agency's chairman.

Navarro, a Harvard-trained economist, served in Trump's first administration, running a newly created National Trade Council and then the White House Office of Trade and Manufacturing Policy.

"During my First Term, few were more effective or tenacious than Peter in enforcing my two sacred rules, Buy American, Hire American," Trump said on his social media platform Truth Social.

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A staunch ally of the president-elect, Navarro was sentenced to four months in prison after a federal jury found him guilty of failing to comply with a subpoena issued by the congressional committee investigating the Jan 6, 2021, US Capitol attack. Shortly after being released in July, he made a speech at the Republican National Convention.

Trump said in his announcement that Navarro was "treated horribly by the Deep State, or whatever else you would like to call it."

Also on Wednesday, Trump announced that Adam Boehler, currently CEO of the healthcare investment firm Rubicon Founders, will be his special envoy for hostage affairs.

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Trump also nominated Jared Isaacman, CEO of Shift4 who has led two private spaceflights, as the next administrator of the National Aeronautics and Space Administration (NASA), and Daniel P. Driscoll, a US Army veteran and venture capitalist, to serve as the secretary of the Army. Both positions would need Senate approval.

Atkins, the CEO & founder of Patomak Global Partners, a risk management consultancy, served as an SEC commissioner from 2002-2008 under President George W. Bush.

The SEC has five commissioners, one of whom is designated as chairman by the president. The president nominates all five commissioners, and their appointments must be approved by the Senate.

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Founded in 1934 at the height of the Great Depression, the SEC's mission is to protect investors, maintain fair, orderly, and efficient markets, and facilitate capital formation.

"Paul is a proven leader for common sense regulations. He believes in the promise of robust, innovative capital markets that are responsive to the needs of Investors, & that provide capital to make our Economy the best in the World," Trump said in a post on his social media platform Truth Social.

"He also recognizes that digital assets & other innovations are crucial to Making America Greater than Ever Before," Trump noted.