US Secretary of State John Kerry said on Monday that Washington will talk with Pyongyang if it takes "meaningful steps" toward peace, as he ended a trip to the region dominated by concerns about Pyongyang's nuclear and missile programs.

"The United States remains open to authentic and credible negotiations on denuclearization, but the burden is on Pyongyang," said Kerry, speaking in Japan on the last leg of an Asian tour that included stops in China and the Republic of Korea.

"North Korea must take meaningful steps to show it will honor commitments it has already made."

The nuclear missile program of the Democratic People's Republic of Korea threatens not only the DPRK's neighbors, but also its own people, Kerry said.

Kerry also met with Japan's Prime Minister Shinzo Abe on Monday, and both Washington and Tokyo urged Pyongyang not to launch a missile.

Kerry continued to take a mild tone toward the DPRK in Japan, and his East Asia trip is a turning point for the situation on the Korean Peninsula, said Wang Junsheng, a researcher on East Asian studies with the Chinese Academy of Social Sciences.

Kerry's comments showed the US doesn't want the situation on the peninsula to spiral out of control, and it has the willingness to communicate with Pyongyang, Wang said. After receiving this message from the US, the DPRK will also show more restraint, he added.

Kerry's visit offers an opportunity to ease tensions on the Korean Peninsula, Wang said.

But Shi Yinhong, a professor on international affairs at Remin University of China, said there are still differences in views among relevant parties.

The Korean Peninsula has been in a state of heightened military tension since the DPRK carried out its third nuclear test in February.

Incensed by fresh United Nations sanctions and joint ROK-US military exercises, Pyongyang has spent weeks issuing blistering threats of missile strikes and nuclear war.