Mattis takes stock of N Korea threat

South Korea and the United States yesterday agreed to push through with the deployment of a US missile defence system strongly opposed by China, the prime minister said.

Hwang Kyo-Ahn and US Defence Secretary James Mattis confirmed that the two allies will go ahead with the installation of the Terminal High Altitude Area Defense (THAAD)system in the South this year as planned, the prime minister's office said.

The two allies last year announced plans to deploy the THAAD system following a series of North Korean atomic and missile tests, infuriating China which fears it will undermine its own ballistic capabilities.

Mattis arrived yesterday in South Korea on the first leg of a trip that also includes Japan, two key allies rattled by US President Donald Trump's ascent to power.

It is the first overseas tour by a senior official in Trump's administration as concerns rise about the direction of American policy in the region under the protectionist and fiery leader.

"President Trump ... wanted me to make a very clear statement about the priority that we place on this alliance between our two allies", Mattis said at the start of his talks with Hwang, who serves as the South's acting leader following the impeachment of President Park Geun-Hye in December over corruption charges.