South Korean special envoy Hwang Joon-kook will meet his Japanese and United States counterparts in Seoul on Wednesday to hold "in-depth talks" on possible diplomatic responses to the North's nuclear weapon test, its first since 2013 and fourth overall.
"This was a demonstration of the ironclad US commitment to our allies in South Korea, in Japan, and to the defense of the American homeland", said PACOM Commander Adm. Harry B. Harris Jr.
"The United States and South Korea are continuously and closely having discussions on additional deployment of strategic assets", Kim Min-seok, spokesman at the South Korean defense ministry, said on Monday, declining to give specifics.
Other strategic assets under consideration reportedly include a USA aircraft carrier, a nuclear-powered submarine and F-22 stealth fighters.
A handout picture provided by the South Korean Air Force on January 11, 2016 shows a US B-52 strategic bomber flying over South Korea with fighter jets from the two countries, over South Korea, January 10, 2016.
The B-52 flew low over an air base close to the North-South border.
The B-52 Stratofortress, a long-range, heavy bomber that can fly up to 15,200 meters (50,000 feet) and has the capability to carry 31,000 kilogram (70,000 pounds) of nuclear or precision guided conventional ordnance, was armed with nuclear missiles and "bunker buster" bombs while crossing South Korean territory.
"A lot of North Korean military commanders find US bombers especially threatening, given the destruction here in Pyongyang during the Korean War, when much of the city was flattened", Ripley said.
Pyongyang claimed Wednesday that it had tested a hydrogen bomb, a thermonuclear device far more powerful than the three atomic bombs the North Korean capital has tested in the past.
South Korea said Monday it will further limit access by its nationals to a joint industrial park in North Korea to ensure their safety following the North's claimed test of a hydrogen bomb last week.
North Korea is likely to engage in new provocations, Gen. Lee Sun-jin, the chairman of South Korea's Joint Chiefs of Staff, said on a visit to Osan Air Base south of here.
The order was announced by Curtis Scaparrotti, the head of United States military deployment in South Korea, who was visiting the Osan airbase, run by Washington and Seoul.
China has signed up for tough United Nations sanctions on North Korea and insists it follows them, including carrying out border inspections, but it also provides large amounts of aid off the books to Pyongyang, experts and diplomats say.
The complex, where South Korean factories employ North Korean workers, is an important source of revenue for the impoverished North.
North Korea says U.S. university student arrested
South Korean-born Canadian pastor Hyeon Soo Lim was sentenced last month to hard labour for life, according to state media. North Korea in the past has sometimes released or deported US detainees after high-profile Americans visited the country.
Warmbier was in North Korea for a five-day trip and was detained at Pyongyang's airport before he boarded a flight back to China
