Feb. 2 (UPI) -- U.S. Secretary of Defense James Mattis arrived in South Korea on Thursday to reassure Seoul of the U.S. commitment to jointly defend against growing North Korea threats, while standing "shoulder to shoulder" with a longtime ally.
U.S. Army Gen. Vincent Brooks, the United States Forces Korea commander, greeted Mattis, who arrived at the U.S. Osan Air Base in Korea shortly after noon Thursday.
South Korea is the first official visit for Mattis, who met with Seoul's national security chief Kim Kwan-jin and told acting president and Prime Minister Hwang Kyo-ahn the North Korea nuclear threat is a top priority for the Trump administration.
"I talked to President Trump and he wanted to make a very clear statement about the priority that we place on the alliance between our two nations," Mattis said, according to Yonhap.
Mattis later attended a dinner held in his honor, hosted by his Seoul counterpart Han Min-koo.
Earlier on the plane Mattis told reporters he would talk to South Korean leaders about the deployment of the U.S. missile defense system THAAD, The New York Times reported.
"I will talk to them about THAAD, absolutely," Mattis said. "It is a defensive system."
China has been vocal in its opposition to THAAD deployment, and has claimed the powerful THAAD radar could be used for monitoring purposes.
South Koreans have also become concerned and many suspect Beijing has been taking retaliatory trade measures against South Korean companies for the decision to deploy the missile defense system.
Seoul has remained committed to the joint decision to deploy THAAD, reached in July 2016. The military is expected to complete deployment in May or June, according to local news service MoneyToday.
South Korea's top diplomat is expected to exchange a phone call with new U.S. State Secretary Rex Tillerson.
Foreign Minister Yun Byung-se is to call for close cooperation against North Korea.
Tensions have grown on the peninsula since Kim Jong Un declared in his annual New Year's speech the country is ready to test-fire an intercontinental ballistic missile.