US warns N Korea of reprisals in nuclear-test showdown
President Barack Obama has warned that America stands "shoulder to shoulder" with its ally South Korea in refusing to accept a nuclearised North Korea.
North Korea has threatened to conduct its fourth nuclear test, possibly while Mr Obama is in the region on a week-long trip.
Mr Park said that a test would trigger the collapse of diplomatic engagement with North Korea through a six-nation process.
The South Korean navy responded by broadcasting radio warnings and firing a series of warning shots before the North Korean ships withdrew.
Such pin-prick provocations are unlikely to cause undue concern to the South, but a new nuclear test would be a significant escalation of the already tense situation in the region.
Earlier yesterday, a South Korean spokesman said the North has completed all preparations for a new test.
Before leaving Tokyo for Seoul, Mr Obama warned that any new nuclear tests would only serve to further isolate the country.
"North Korea has engaged in provocative actions for the last several decades," the president said. "It has been an irresponsible actor on the international stage for the last several decades. They are the most isolated country in the world. They are subject to more international sanctions and international condemnation than any country in the world."
Mr Obama said he was not optimistic about a major shift in Pyongyang's attitude in the near future, but he expressed confidence that by working with South Korea, Japan and China that "more pressure" can be brought to bear.
On Thursday, UN general secretary Ban Ki-moon called on Pyongyang to cancel plans for the "new form" of nuclear test.
China, North Korea's only significant ally, also issued a thinly veiled warning to the regime of Kim Jong-un, with a spokesman for the foreign ministry in Beijing telling reports that it would not permit "war or chaos to occur on our doorstep". (© Daily Telegraph, London)