A US nuclear-powered aircraft carrier left a naval base in California last week for a deployment to the Indo-Pacific region, a US research institute has said, while another carrier was already in South Korea in a major show of force.

In a report, the US Naval Institute cited a Navy official as saying USS Carl Vinson (CVN-70) departed from Naval Air Station North Island, California, on Thursday. USS Ronald Reagan (CVN-76) arrived in South Korea's southeastern port city of Busan on Thursday for a five-day visit.

The deployment comes amid concerns that the United States' security focus on the escalating Israel-Hamas war could lead to a weakening of its security commitments to South Korea and other regional partners.

USS Carl Vinson is currently conducting "routine" operations in the US 3rd Fleet area of operations, according to the fleet.

"US 3rd Fleet works together with our allies and partners to advance freedom of navigation, the rule of law, and other principles that underpin security for the Indo-Pacific region," the fleet was quoted by the USNI as saying in a statement.

After the Hamas militant group's surprise attack on Israel on Oct. 7, Washington deployed the USS Gerald R. Ford (CVN-78) Carrier Strike Group to the Eastern Mediterranean. It also moved the USS Dwight D. Eisenhower (CVN-69) Carrier Strike Group to the region to "deter hostile actions against Israel or any efforts toward widening this war," according to the Pentagon. (Yonhap)