The United States and Japan on Tuesday made a fresh warning to North Korea to drop plans for a missile launch, with barely a week to go before the communist state's threatened plans.

"Any kind of missile launch of any kind is of great concern and would be a violation, in our view, of UN Security Council resolutions," State Department spokeswoman Victoria Nuland told reporters.

US Defense Secretary Leon Panetta and Japanese Defense Minister Naoki Tanaka discussed North Korea's plans in a telephone call and "affirmed the importance" of their two nations' alliance in defending Japan.

Tanaka and Panetta "reiterated their view that such a missile launch would directly violate North Korea's international obligations," a Pentagon statement said.

North Korea has said that it will launch a "satellite" between April 12 and 16 as it holds "unprecedented" celebrations to mark the 100th anniversary of the birth of the regime's founder Kim Il-Sung.

The communist state announced the plans despite agreeing on February 29 to freeze its nuclear and missile programs as part of a deal under which the United States would deliver badly needed food aid.