(CNN) -- U.S. Secretary of State John Kerry said Monday that North Korea must stop "bucking the trend of history and common sense" in continuing with its nuclear program and that any unilateral action by the North "carries too great a cost" for the world to allow it.
Kerry spoke at the end of a three-day trip that focused on securing fresh commitments from South Korea, China and Japan for denuclearization on the Korean Peninsula and getting Pyongyang back to the negotiating table.
"The United States remains open to authentic and credible negotiations on denuclearization, but the burden is on Pyongyang," Kerry said in Tokyo. "Korea must take meaningful steps to show it will honor commitments it has already made" and the norms of international law.
Last month, North Korea scrapped the 1953 truce that effectively ended the Korean war and said it was nullifying the joint declaration on the denuclearization of the Korean Peninsula.
It also recently pledged to restart its Yongbyon nuclear complex, including a uranium enrichment plant and a reactor that was shut down under an agreement reached in October 2007 during talks with North Korea, the United States, and four other countries.
"The world does not need more potential for war, so we will stand together. And we welcome China's strong commitment ... to the denuclearization of the Korean Peninsula," Kerry said.
"The stakes are far too high and the global economy is far too fragile for anyone to allow these inherited problems to divide the region and inflame it."
A U.S. State Department official said Monday there are no plans to move toward direct talks, however, "because North Korea has shown no willingness to move in a positive direction."
Pyongyang on Sunday rejected a different proposal for dialogue, one by South Korea last week regarding the North's suspension of activity at the manufacturing zone that the two countries jointly operate.
A statement via KCNA, the state-run news agency, called the South's offer a "crafty trick" and "empty words without any content."
A KCNA commentary Monday was titled, "U.S. is to blame for escalating tension on Korean Peninsula."
Kerry's trip finishes on one of the biggest dates on the North Korean calendar: "The Day of the Sun," when citizens celebrate the birthday of the country's late founder and "eternal president," Kim Il Sung. This year marks his 101st birthday.
Current leader Kim Jong Un paid tribute Monday to Kim Il Sung, his grandfather, as well as his late father, Kim Jong Il, visiting the halls where both men lie in state. It was believed to be Kim's first public appearance in two weeks.
Amid the pageantry, patriotism and festive images being played on North Korean state television Monday, many around the world wonder whether this will also be the day North Korea decides to launch a missile, perhaps in a show of bravado after weeks of nuclear threats.
Some scholars say a launch is still possible, if not Monday, then in the coming days. CNN Correspondent Kyung Lah reports from Seoul that because April 15 is the founder's birthday, North Korea would not conduct a missile launch then with the possibility of failure hanging over them.
Pyongyang made good on its promise to launch a long-range rocket around the time of Kim Il Sung's birthday last year; the rocket broke apart after launch and fell into the sea.
North Korea has made more threats since then. It launched a rocket in December that apparently put a satellite into orbit, and in response, the U.N. Security council approved broadening sanctions against the country.
Angered by those sanctions, Pyongyang announced in January it was planning a new nuclear test and more long-range rocket launches as part what it called a new phase of confrontation with the United States.
It carried out an underground nuclear bomb test in February, and last month, Pyongyang threatened for the first time to launch a pre-emptive nuclear strike against the United States and South Korea.
The North also threatened to attack U.S. and South Korean bases.
CNN's Jill Dougherty contributed to this report.