In an explicit acknowledgment that North Korea may be planning a long-range missile test, South Korea's top diplomat has publicly urged Pyongyang to set any such plans aside. While expectations of the test mount, the North continues to boycott talks on giving up its nuclear weapons programs.

South Korean Foreign Minister Ban Ki-moon says North Korea should be focusing more on talking about its nuclear weapons programs - and less on testing its missiles.

Ban tells reporters it is appropriate for North Korea to set aside apparent plans for a long-range missile test, and return to six-party talks.

Five partner nations: South Korea, the United States, Japan, Russia and China - have been trying unsuccessfully for three years to persuade North Korea to abandon nuclear weapons.

Ban's comments on Wednesday followed days of international media reports quoting anonymous intelligence officials as saying there is reason to believe the North may be preparing to test an intercontinental missile.

South Korean authorities downplayed those reports at first, but Lee Tae-sik, South Korea's ambassador to the United States, acknowledged Tuesday that test preparations did appear to be under way.

North Korea is already capable of reaching its neighbors with existing missiles. Pyongyang shocked Japan by firing a medium-range missile directly over Japan's main island in 1998.

U.S. experts fear North Korea's long-range Taepodong-2 missile - the one reportedly being readied for a test - might be able to reach the Western United States. The experts say such a test would only heighten Washington's perception of the North as a direct threat.

Analysts say advanced missile testing could also push forward the time when North Korea could theoretically deliver a nuclear device as a missile warhead - a capability the communist state is not currently believed to possess.

North Korea has refrained from long-range missile testing under a self-imposed moratorium since 1999.

South Korean Ambassador Lee, in Washington, has cautioned that Pyongyang's apparent preparation to abandon that moratorium could just be a maneuver to pressure Washington into making diplomatic concessions.

North Korea is refusing to return to the six-party nuclear talks unless Washington drops financial sanctions that U.S. officials say are necessary to protect U.S. interests from North Korean money laundering and counterfeiting.