Seoul, Oct 27 (IANS): US Defence Secretary James Mattis on Friday arrived at the Demilitarized Zone (DMZ) between North and South Korea, on the first day of his visit to Seoul.

Mattis will visit Observation Post Ouellette at the heavily-guarded border, where he will be briefed by US and South Korean Joint Security Area Commanders Lt. Col. Matthew Farmer and Lt. Col. Kwon Young-hwan, reports CNN.

Earlier on Friday, Mattis visited two US military installations, Osan airbase and the Yongson garrison in Seoul.

The secretary had come to South Korea from Thailand, where he attended the funeral of late King Bhumibol Adulyadej on Thursday.

Mattis' trip to the region comes ahead of US President Donald Trump's visit to Asia next week.

Trump will most likely forgo a visit to the heavily fortified border between North and South Korea, a senior White House official said earlier this week, CNN reported.

Citing scheduling conflicts in an already jammed itinerary, the official did not rule out entirely a visit to the demilitarized zone.

But, speaking to reporters, the official downplayed the importance of stopping at the DMZ, which the past three US Presidents have visited during trips to South Korea.