High-ranking officials from the United States and several Asian nations urged North Korea not to conduct a widely anticipated ballistic missile test, warning that a launch could derail efforts to improve the isolated Stalinist state's relations with the rest of the world.

Defense Secretary William S. Cohen told reporters on a flight to Japan that a launch by North Korea would have "serious implications" for its relationship with the United States and for a multibillion-dollar U.S. program to construct light-water nuclear reactors in the North.

Concern over North Korea's missile program also was on the minds of the 10 Southeast Asian foreign ministers and their counterparts from several industrialized countries, including Secretary of State Madeleine K. Albright, who were meeting in Singapore for regional security talks. A Japanese spokesman at the meeting said any new missile firing would have "a negative impact on regional security."

The statements of concern came as a North Korean Foreign Ministry official was quoted by the Korean Central News Agency as warning that Washington's policy of "isolating and stifling" North Korea had left "no option but to increase our own capabilities and develop missiles as its means."

The news agency dispatch blamed the Clinton administration for heightened tension in East Asia, saying the U.S. policy of linking the missile tests to the development of the nuclear reactors had threatened the entire program. The program was instituted in 1994, when North Korea agreed to freeze its nuclear program in return for $5 billion worth of free fuel and light water nuclear reactors, which could not be used to generate weapons-grade plutonium.

North Korea stunned the world last August when a test launch of its new Taepodong missile sent the three-stage missile over Japan and into the Pacific Ocean. With fears rising that another test is likely, if not imminent, Japan recently threatened to withhold a $1 billion contribution to the nuclear program consortium. Military analysts said a Taepodong II rocket believed to be in the works and ready for testing could reach Alaska or Hawaii.

En route to Japan for a trip that will largely focus on the new tension on the Korean peninsula, Cohen said a new test "would have serious implications for the nature of the relationship that we currently have with the North Koreans." Cohen said he hoped to use his week-long trip to Tokyo and Seoul to build "solidarity of our policy toward North Korea."

His concern was echoed in Singapore by Albright, who said, "Our hope is that nations will join in urging North Korea to respond positively to the choice North Korea now has to end its isolation."

Another North Asian regional trouble spot, Taiwan, also was on the agenda for discussion at the Singapore meeting. President Lee Teng-hui has riled China by asserting that future dealings between Taipei and Beijing will be conducted on a "state-to-state" basis. That rejection of the long-standing "one China" policy is seen by Beijing as a dangerous step toward a declaration of independence by Taiwan, which it sees as a renegade Chinese province.

Chinese Foreign Minister Tang Jiaxuan said again today that China would not rule out the use of force if Taiwan took a full step toward independence. He told the regional meeting in Singapore that "China's territory and sovereignty are indivisible and brook no violation or interference."

Albright and her Russian counterpart, Igor Ivanov, also used today's gathering in Singapore to discuss matters on the other side of the globe. Both said they hoped to move beyond the divisions that the Kosovo crisis caused between Moscow and Washington, and Ivanov reaffirmed Moscow's commitment to a "partnership relationship" with the United States.