U.S. Secretary of State John Kerry arrived in Japan on Sunday, the last stop on an Asian tour aimed at solidifying support for curbing North Korea's nuclear programme and reassuring U.S. allies after weeks of threats of war from Pyongyang.
Kerry's talks with his Japanese counterpart, Fumio Kishida, coincide with preparations for the North's biggest holiday of the year on Monday, the Day of the Sun, the birth date of state founder Kim Il-Sung - an occasion for pomp and perhaps a military display.
The North's state media, one of the few ways of glimpsing what is happening in the reclusive country, have so far ignored Kerry's talks in Beijing and Seoul.
But in addition to reports on the festivities, they have issued new denunciations of U.S. policy and made it plain North Korea has no intention of giving up its nuclear weapons, described as the "treasured" guarantor of the North's security.
The South Korean capital, Seoul, displayed the calm it has shown throughout the crisis. Residents strolled in bright sunshine, visiting street bazaars, ancient temples and walking in the hills.
The North has threatened for weeks to attack the United States and South Korea since new U.N. sanctions were imposed in response to its latest nuclear arms test in February. Speculation has mounted of a new missile launch or nuclear test.
On Saturday, Kerry met top leaders in China, the North's sole diplomatic and financial benefactor, and said both sides were committed to "the denuclearization of the Korean peninsula in a peaceful manner".
During his first stop in Seoul, Kerry said North Korea, also furious at joint U.S.-South Korean military drills currently under way, would be making a "huge mistake" if it launched one of its medium-range missiles during the current standoff.
He also said China was in a position to influence the North's policy and had to put "some teeth" into efforts to persuade Pyongyang to alter its policies.
Japan, separated by less than 1,000 km (625 miles) of water and a frequent target of North Korea's anger, is in easy range of North Korea's medium-range missiles.
Japanese news reports said Tokyo had sent Aegis-class destroyers capable of missile interception to the Sea of Japan. Patriot Advanced Capability-3 interceptor missiles have been deployed at key locations in the capital and surrounding areas.
Japanese Defence Minister Itsunori Onodera told reporters on Sunday it was important to communicate to North Korea that it must abandon nuclear and missile development.
In Beijing, Kerry said that if North Korea abandoned its nuclear capabilities, the United States would have no reason to maintain recently deployed defensive capabilities - like new or expanded missile defence systems in Alaska and Guam.
"Now, obviously, if the threat disappears, i.e. North Korea denuclearizes, the same imperative does not exist at that point in time for us to have to have that kind of robust, forward leaning posture of defence."
North Korea's KCNA news agency, quoting the Committee for the Peaceful Reunification of Korea, said the South, where 28,000 U.S. soldiers are based, had committed "another unpardonable hideous provocation that ... insults the celebrations of the Day of the Sun".
"The more desperately the enemies make vituperation, the stronger (North Korea's) will for retaliation will become, and the moment when it is given full play, the group of traitors will be wiped out to the last man from this land," it said.
It was not immediately clear what the provocation was.
Kerry's agenda in Tokyo is also likely to focus on discussions on Japan's territorial disputes with China and the future of U.S. bases in Japan.
The United States and Japan this month announced an agreement for the return to Japan of a U.S. air base, taking a step to resolving an issue that has long troubled relations.