Tokyo ? The United States and Japan urged North Korea not to proceed with reported plans to test-fire a long-range missile that could reach the U.S. mainland, saying Saturday that a launch would be dangerous and provocative.

But North Korean officials later denied such preparations, the Kyodo News agency reported, citing a South Korean official it did not identify.

U.S. Ambassador to Japan Thomas Schieffer and Japanese Foreign Minister Taro Aso met Saturday night amid mounting speculation the North could soon test a Taepodong-2 missile capable of reaching the United States with a light payload.

South Korean media reports said the North had loaded booster rockets onto a launch pad in preparation for the test.

After the meeting, Schieffer reiterated Washington’s stance that the test would be a dangerous act that would hurt North Korean interests.

The North has been under a self-imposed moratorium on long-range missile tests since 1999.