Defense chiefs of South Korea and the United States on Tuesday reaffirmed the planned deployment of an advanced missile defense system this year to counter growing threats from North Korea.

Defense Minister Han Min-koo and US Defense Secretary James Mattis talked over the phone to confirm that the Terminal High Altitude Area Defense system will be placed in South Korea this year as scheduled and the allies will maintain full readiness to counter any aggression by the North, the Ministry of National Defense said in a statement.

The 30-minute phone conversation came amid heightened tensions on the Korean Peninsula after North Korean leader Kim Jong-un threatened in his New Year's Day address to test-fire an intercontinental ballistic missile capable of reaching the US mainland.

Mattis is scheduled to visit South Korea from Thursday to Friday before flying to Japan, the ministry said.

He will meet Han at the ministry's headquarters in Seoul on Friday morning after meetings with Acting President and Prime Minister Hwang Kyo-ahn and National Security Office chief Kim Kwan-jin a day earlier, it said.   

The secretary will also hold a separate meeting with Foreign Minister Yun Byung-se reportedly on Friday to discuss North Korea's nuclear and missile threats as well as ways to enhance the countries' alliance. 

"The latest talks are expected to become a good opportunity to enhance Secretary of Defense Mattis' understanding on the importance of the South Korea-US alliance as well as North Korean nuclear issues," foreign ministry spokesman Cho June-hyuck said.

Mattis chose to visit South Korea as the US takes the North's evolving nuclear and missile programs as a serious threat to security on the Korean Peninsula and in the Asia-Pacific region, it said.

"Mattis' decision to visit Seoul for his first overseas trip after being appointed as defense secretary (on Jan. 20) will deliver a very timely and stern message to North Korea," Han said in the statement. 

Seoul and Washington agreed last year to station a THAAD battery in South Korea.

But China has explicitly expressed opposition to the deployment, claiming the move will hurt their strategic security interests. Beijing has maintained the system's powerful X-band radar can spy on its military activities. 

The United States has repeatedly stressed that the system is purely defensive in nature and aimed only at deterring North Korean threats.

In Washington, Pentagon spokesman Capt. Jeff Davis said that Mattis reaffirmed the "US commitment to defend the ROK and provide extended deterrence using the full range of US capabilities."

"The two affirmed that the US-ROK alliance of more than 60 years remains even more relevant today and determined to take steps to strengthen the alliance further to defend against the evolving North Korean threat," Davis said in a readout.

"Secretary Mattis recognized the significance of the US-ROK alliance, noted that his visit to the ROK and Japan will be his first overseas trip during his tenure as secretary of defense, and conveyed that the US will stand shoulder-to-shoulder with the ROK forces," he said.

Last year alone, Pyongyang conducted two nuclear tests and test-fired 24 ballistic missiles to achieve its stated goal of developing a nuclear-tipped long-range ballistic missile that could hit the US mainland. (Yonhap)