President-elect Donald Trump on Tuesday announced more nominations for high-level officials in his upcoming administration.

While Trump has already nominated candidates to serve in most of the top-level cabinet roles, there are still administration positions unfilled that will be closely involved with trade, public health and domestic policy.

Trump's nominations on Tuesday include:

United States Trade Representative

Jamieson Greer worked in the first Trump administration as chief of staff to Robert Lighthizer, then the U.S. Trade Representative. The cabinet-level position is responsible for developing and executing foreign trade policy for the U.S. Greer's nomination is subject to Senate approval.

Director of the National Institutes of Health

Dr. Jay Bhattacharya, currently a professor of health policy at Stanford University, is nominated to oversee medical research the National Institutes of Health. The officer works alongside the secretary of health and human services to set research goals and ensure the budget and resource needs of the NIH are met. The position is subject to Senate confirmation.

Deputy Secretary of Health and Human Services

Jim O'Neill is a technology investor and previously served in several health-related policy roles, including as the principal associate deputy secretary of HHS. From 2008 to 2012, he was the managing director of Thiel Capital. Trump says O'Neill will focus on "management, transparency and accountability" at HHS. His nomination is subject to Senate approval.

Director of the White House National Economic Council

Kevin A. Hassett was the Chairman of the Council of Economic Advisers during Trump's first term. The office he is nominated for coordinates domestic and international economic policy across government agencies and advises the president on enacting those policies. Trump says Hassett will work to ensure fair international trade and "renew and improve our record tax cuts." The position is not subject to Senate approval.

Secretary of the Navy

Businessman John Phelan is nominated to oversee the operations of the U.S. Navy and the U.S. Marine Corps. The naval secretary reports to the secretary of defense and is responsible for directing branch recruitment, training and mobilization and the construction and provisioning of Navy vessels and installations. By law, if a nominee for secretary of the Navy served in the military, they must be a civilian for at least five years before nomination. Phelan has not served in the U.S. military. Phelan's nomination is subject to Senate confirmation.

Director of the Domestic Policy Council

Vince Haley served as a speechwriter during Trump's first term. The office he is nominated for directs domestic policy and coordinates other federal offices in achieving those goals. The position is not subject to Senate confirmation.

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