Japan was on a state of high alert last night after a senior North Korean official declared that Pyongyang was not bound by a 2002 moratorium on testing long-range missiles.
The North Korean threat follows days of escalating tension prompted by evidence that Pyongyang is preparing to test a missile that could reach Japan and parts of the continental US.
Ri Pyong Dok, a North Korean foreign ministry official responsible for Japan, told Japanese journalists in Pyongyang, Kyodo news reported, that a long-range missile test launch "is not bound by any statement such as the Pyongyang Declaration".
Mr Ri was referring to an agreement signed in 2002 between Kim Jong Il, North Korea's leader, and Junichiro Koizumi, Japan's prime minister, in which Pyongyang promised not to test long-range missiles.
John Bolton, US ambassador to the United Nations, said members of the Security Council had begun "preliminary" discussions on how to respond to any test.
"We are discussing a range of things that fall within the Security Council's domain given that this launch would constitute a threat to international peace and security," Mr Bolton said in Washington.
US officials said yesterday that the US had activated its missile defence system but some analysts questioned whether the system would be capable of hitting an incoming missile. Bryan Whitman, Pentagon spokesman, said: "The US does have a limited missile defence system but I'm not going to get into specific alert status or capabilities."
Dominique de Villepin, the French prime minister, yesterday said the international community should respond to a North Korean test with a "firm and just" response.
A US official on Monday said Washington believed North Korea had fuelled the Taepodong-2 missile, a procedure that is difficult and dangerous to reverse, suggesting that a missile test could be imminent. Some media reports have suggested that bad weather over the launch site in the north-east of the nation could be delaying the launch.
Pyongyang caused an international crisis in 1998 when it fired an earlier version of the Taepodong missile over Japan into the Pacific. The event was a catalyst for Tokyo's decision to develop a missile defence shield in conjunction with Washington.
Both Mr Koizumi and Shinzo Abe, Japan's chief cabinet secretary who has made his career being tough on North Korea, said this week that Japan would respond sternly to any missile test. Taro Aso, the foreign minister, told a television programme that if a missile entered Japan, it would be regarded as an attack.
Additional reporting by Alex Kliment in Washington
