US Secretary of State John Kerry on Sunday stressed the United States is willing to engage with North Korea as long as it takes steps to give up nuclear weapons.

He also vowed the United States would protect its Asian allies against any provocative acts by the North, but said Washington wants a peaceful solution to rising tensions in the region.

"We are prepared to reach out but we need (the) appropriate moment, appropriate circumstance," Kerry said, adding that North Korea had to take steps towards giving up its nuclear programs.

"I think it is really unfortunate that there has been so much focus and attention in the media and elsewhere on the subject of war, when what we really ought to be talking about is the possibility of peace. And I think there are those possibilities," Kerry earlier told a news conference in Tokyo after a meeting with his Japanese counterpart, Fumio Kishida.

Kerry said the United States would "do what was necessary" to defend its allies Japan and South Korea, but added, "Our choice is to negotiate; our choice is to move to the table and find a way for the region to have peace."

Kerry also sought to clarify his comments made in Beijing on Saturday, which some took to suggest he might be offering to remove recently boosted missile defense capabilities in Asia if China persuaded North Korea to abandon its atomic programs.

"The president of the United States deployed some additional missile defense capacity precisely because of the threat of North Korea. And it is logical that if the threat of North Korea disappears because the peninsula denuclearizes, then obviously that threat no longer mandates that kind of posture. But there have been no agreements, no discussions, there is nothing actually on the table with respect to that," Kerry noted.

Reuters