The Group of Eight powers on Thursday demanded that North Korea drop plans for a rocket launch as the United States warned that defiance would lead to action at the UN Security Council.
The club of major industrial nations made the show of unity despite widespread doubts that North Korea can be dissuaded to call off firing the rocket, which is expected to fly into the East China Sea within days or even hours.
The Group of Eight foreign ministers "demand that the DPRK not conduct the launch," said an unusually strongly worded statement after talks in Washington, referring to the North by its official name, the Democratic People's Republic of Korea.
North Korea has said that it will launch its Unha-3 (Galaxy-3) rocket by Monday to put a satellite into orbit as the world's only communist dynasty celebrates the centennial of the birth of its founder Kim Il-Sung.
But the statement released by the United States after talks of the Group of Eight -- which includes all veto-wielding members of the UN Security Council except North Korea's main ally China -- described the plan as a missile launch.
Secretary of State Hillary Clinton said there was "no doubt" the launch would use ballistic missile technology -- a violation of UN Security Council resolution approved in 2009 -- and warned North Korea it faced a "clear choice."
"It can pursue peace and reap the benefits of closer ties with the international community, including the United States, or it can continue to face pressure and isolation. If Pyongyang goes forward, we will all be back in the Security Council to take further action," Clinton told reporters.
Clinton said that such a path would be regrettable, noting that the United States had agreed just weeks earlier to deliver food aid to the impoverished state in return for its pledges to freeze its nuclear and missile programs.
"But in the current atmosphere, we would not be able to go forward with that, and other actions that other countries had been considering would also be on hold," Clinton said.
The State Department announced that Kurt Campbell, its top official on East Asia, would leave Saturday to consult with South Korea and Japan, treaty-bound US allies that are arch-enemies of North Korea.
Clinton said there was agreement over "additional steps" by the Group of Eight -- Britain, Canada, France, Germany, Italy, Japan, Russia and the United States -- as well as by the five nations in moribund denuclearization talks with North Korea, which include China.
But it remained unclear what action the Security Council would take as North Korea is already one of the world's most sanctioned and isolated nations.
A pro-North Korean newspaper in Japan, along with South Korean intelligence, have both held out the possibility that Pyongyang would carry out a new nuclear test if tensions mount over its rocket launch.
Privately, some policymakers have said that the best approach may be to stress international unity at the Security Council but to take an understated approach so as not to fan the flames.
Japanese Foreign Minister Koichiro Gemba, who met Thursday with US Defense Secretary Leon Panetta after the Group of Eight talks, has also called for unspecified "appropriate action" by the Security Council if Pyongyang carries out the launch.
Japanese foreign ministry spokeswoman Naoko Saiki said it was undecided if the Security Council would pursue a new resolution, issue a statement -- which carries less legal force -- or take other action.
"At this moment, utmost efforts must be done to urge North Korea not to launch a missile," she told reporters.
"Without going into intelligence or concrete evidence, I could say that we have to be prepared for the worst scenario in which North Korea might take further provocative actions including a nuclear test," she said.
"In order to prevent that from occurring, I think the international community must act in unity," she said.
China has taken the rare step of publicly criticizing North Korea for its planned launch but has also called on all countries to "exercise restraint" after Washington urged Beijing to exert more pressure.