Yielding to North Korea's latest nuclear threats without further dialogue and pressure would be unwise, Japanese and American delegates involved in talks on the North's denuclearization agreed Monday in Tokyo.

"This is not the first time the North has committed a provocative act," Akitaka Saiki, Japan's chief delegate on the denuclearization talks, told reporters after his meeting with U.S. envoy on North Korean policy Stephen Bosworth. "We will act calmly and without haste."

Pyongyang has reportedly restarted its plutonium-producing reactor in Yongbyon following its announcement it was dropping out of the six-party talks. The reclusive state has reacted with a clenched fist to widespread criticism of its rocket launch — widely believed to have been a disguised ballistic missile test — last month and is thought to be readying its first nuclear test since 2006.

Nevertheless, Saiki said he and Bosworth agreed the six-party talks, with China as the chair, are vital to achieving a denuclearized North Korea.

Visiting Tokyo following North Korean criticism of U.S. policy, Bosworth stressed that the U.S. does not believe that a rash response to the threats will lead to the ultimate goal of denuclearization.

"Washington is fully aware and we are on the same page there," Saiki said, referring to the consensus among Japan, the U.S., Russia, China and South Korea to adopt the U.N. Security Council's presidential statement on the rocket launch.