U.S. Senator Andy Kim (D-NJ) is ceremonially sworn into office by Vice President Kamala Harris during a re-enactment in the Old Senate Chamber on the first day of the 119th Congress at the U.S. Capitol in Washington, U.S., Jan. 3. Reuters-Yonhap

Andy Kim, the first-ever Korean American senator, reaffirmed his commitment Friday to being a "bridge" between South Korea and the United States and to promoting the two countries' prosperity and security as he stressed a "strong U.S. requires strong partnerships and alliances."

Kim made the remarks as the 119th Congress kicked off amid expectations that the new senator will play a key role in cementing the Seoul-Washington alliance in the midst of shared challenges, including North Korea's evolving nuclear and missile threats.

In November, Kim won the Senate seat for New Jersey that was up for grabs as former Sen. Bob Menendez resigned in August following his conviction on bribery charges. Kim took office last month, succeeding George Helmy who was appointed in August to succeed Menendez.

"A strong United States requires strong partnerships and alliances, and I remain committed to being a bridge between the United States and South Korea, and to advancing our shared prosperity and security," Kim said in a statement provided to Yonhap News Agency.

He also highlighted his commitment to working for the American people, while showing his sense of honor to serve in the upper chamber of Congress.

U.S. Senator Andy Kim (D-NJ) introduces his father to Vice President Kamala Harris after being ceremonially sworn into office by Harris during a re-enactment in the Old Senate Chamber on the first day of the 119th Congress at the U.S. Capitol in Washington, U.S., Jan. 3. Reuters-Yonhap

"I'm humbled to take the oath of office to serve the state that raised me in the United States Senate. The son of Korean immigrants, growing up I could not have imagined this honor," he said.

"We have critical work ahead in the 119th Congress to bring needed change to make our democracy work for the people and give everyone a chance at the American dream."

The new senator is to sit on four Senate committees: Commerce, Science and Transportation; Banking, Housing and Urban Affairs; Health, Education, Labor and Pensions; and Homeland Security and Governmental Affairs.

Kim was born in Boston in 1982 to a family of South Korean immigrants -- his father being a medical researcher and his mother a nurse.

The senator boasts a prominent foreign policy portfolio, having served at the White House National Security Council, the Pentagon, the State Department, the U.S. Agency for International Development and as a civilian adviser to Gen. David Petraeus and Gen. John Allen in Afghanistan.

Kim earned a political science degree from the University of Chicago in 2004. He was awarded a prestigious Rhodes Scholarship and a Harry S. Truman Scholarship, which led him to earn a master's degree and a doctorate in international relations from the University of Oxford.

As the new Congress began, the House voted to reelect Republican Rep. Mike Johnson — a figure endorsed by incoming President Donald Trump — as its speaker. The vote was seen as the first test of Trump's grip on the GOP that has a thin majority in the House.

In Congress, the Republican Party controls 53 of 100 seats in the Senate and 219 of 435 seats in the House as a result of the November election.

The fragile majority in both chambers has raised questions over whether the legislature will help smoothly enact his "America First" policy agenda, including border security, or keep him in check. (Yonhap)