The United States said Friday a North Korean test firing of a long-range ballistic missile would be a provocative act, and counter to Pyongyang's own interests. U.S. officials have been quoted this week as saying preparations by North Korea to launch a missile with inter-continental range have been observed.

The Bush administration has served notice on North Korea that it would consider a long-range missile firing a provocative act, and it says U.S. officials are urging countries in the region to try to talk Pyongyang out of going ahead with such a test.

The State Department went public with U.S. concerns following reports in the Japanese news media in recent days that there have been signs of preparations for a missile test since early last month.

At a news briefing, State Department Spokesman Sean McCormack would not say what information the United States has gathered about test preparations. But he made clear U.S. officials take the matter seriously, and that efforts are being made to dissuade North Korea from going ahead.

"In recent days, we have been consulting with friends and allies in the region and elsewhere. Together, our diplomacy and that of our allies has made clear to North Korea that a missile launch would be a provocative act that is not in their interests and will further isolate them from the world," he said.  "A North Korean missile launch would be inconsistent with the 1999 moratorium declared by Kim Jong-Il, which he reaffirmed in 2002."

A long-range missile test would be North Korea's first since 1998, when it fired one of its Taepodong long-range missiles over Japan into the Pacific.

Japanese news reports suggest the missile that could be tested within weeks is a multi-stage version of the Taepodong that theoretically could reach parts of the United States.

Spokesman McCormack said the United States would see a missile launch as inconsistent with last September's statement of principles from the six-party talks on North Korea's nuclear program, which spoke of joint efforts for lasting peace and stability in northeast Asia.

In the September statement, North Korea said it was willing in principle to give up its nuclear weapons ambitions in exchange for aid and security guarantees from other parties to the talks, which include China, Japan, Russia and South Korea, as well as the United States.

The six-party talks have been idle, however, since a brief round in Beijing last November.

A senior official who spoke to reporters here said the United States has had no direct contact with North Korea on the possible missile test, but that U.S. views had been conveyed by countries with the most potential influence on Pyongyang, including China, South Korea and Japan.

He said the broad concern about North Korea's missile activity shows that it is not an issue between the United States and North Korea, but rather one between Pyongyang and the rest of the world.

McCormack said the United States has the technical means to monitor and track any North Korean test and, as he put it, protect ourselves.