Japan has given a warning it would launch a pre-emptive military action against North Korea if it had firm evidence Pyongyang was planning a missile attack.
Defence Minister Shigeru Ishiba said it would be "a self-defence measure" if North Korea was going to "resort to arms against Japan".
Mr Ishiba said it would be too late if a North Korean missile was already on its way.
His remarks were the latest in the international row over Pyongyang's nuclear intentions, and followed a North Korean warning that it had the ability to strike American targets anywhere in the world, if provoked.
Click here to see North Korea's missile strike range
Pyongyang was responding to a statement by the head of the US Central Intelligence Agency, George Tenet, warned that Pyongyang had a long-range missile capable of reaching the west coast of America.
On Wednesday, the United Nations nuclear watchdog resolved to refer North Korea to the UN Security Council for breaching nuclear non-proliferation agreements.
Warning
A senior official in Pyongyang, Ri Kwang-hyok, told the AFP news agency that North Korea was capable of attacking "all military personnel and all military commands of the United States in the world" as a self defence measure.
He also called on the Security Council to investigate the United States' own nuclear programme.
"We insist that the responsibility of the US must be discussed too," he said.
North Korea has long been thought to have a missile under development capable of hitting the western United States.
'Chronic offender'
The International Atomic Energy Agency (IAEA) decision on Wednesday to refer North Korea to the UN Security Council brings the nuclear crisis to a new stage.
It raises the possibility of economic and political sanctions against Pyongyang - a move North Korea says it would regard as a declaration of war.
Under its charter, the IAEA must report any violations of the nuclear non-proliferation treaty to the Security Council, and Pyongyang had been in "chronic non-compliance since 1993", IAEA chief Mohamed ElBaradei said.
He said North Korea was only a "month or two" from producing "a significant amount of plutonium" that could be used to make nuclear weapons.
Despite issuing the referral, Mr ElBaradei insisted that the IAEA would continue to press for a peaceful solution to the crisis.
"All members made it clear it is not the time to jump to sanctions," Mr ElBaradei said.
'Window of opportunity'
Pyongyang's neighbours have reacted with concern to the new developments.
South Korea urged Pyongyang to seize the "window of opportunity" left open to it.
It also said it hoped the Security Council would "handle the issue in a way that prevents a worsening of the situation and facilitates a diplomatic resolution".
China, while backing the decision by the IAEA's 35-country board, warned the Security Council against getting involved.
"The UN Security Council's involvement at this stage might not necessarily contribute to the settlement of the issue," China's ambassador to the UN, Zhang Yan, said on Thursday.
"The only correct and effective approach... is through constructive dialogue and consultations on the basis of equality," he said.
Comment