New York - The five veto-wielding powers and Japan continued wrestling Monday over Japan's insistence on a sharpened UN resolution against North Korea for testing a ballistic missile over the weekend.

The UN ambassadors from the United States, Russia, China, France and Britain held their second negotiating session with Japan since Sunday, when a three-hour session of the full Security Council ended with no results.

Tokyo requested the emergency Security Council sessions after Pyonyang sent a missile over Japanese territory that fell into the Pacific Ocean, according to US and Japanese officials. North Korea insists it put a satellite into orbit, but no evidence of the orbiter has been found.

Japanese UN Ambassador Yukio Takasu pushed Monday for a clear directive to Pyongyang that it violated a 2006 UN resolution that forbade North Korea to test ballistic missiles.

Takasu argued that the long-range missiles threaten not only Japan but also the security of the international community.

Beijing and Moscow are reluctant to rule that a violation occurred and have warned against escalating tensions over the disagreement.

On Monday in Washington, US State Department spokesman Robert Wood warned that the matter was "complicated" and beset by "difficult diplomacy" in the search for agreement on a strong, effective international reaction. (dpa)