North Korea has defied the United States and other world powers by test-firing a ballistic missile early on April 29.
U.S. and South Korean officials said the launch from an area north of the capital, Pyongyang, appeared to have failed, as did other recent attempts.
South Korean officials said the missile disintegrated within minutes of being launched and did not leave North Korean territory.
The test-firing came amid U.S. efforts to harness global support to dissuade Pyongyang from carrying out such launches.
After being told about the missile launch at the White House, U.S. President Donald Trump said in a tweet that North Korea had "disrespected the wishes of China and its highly respected president," a reference to recent warnings by China to North Korea that any further nuclear arms tests would lead Beijing to impose more sanctions.
China's official Xinhua news agency said in a commentary on April 29 that both North Korea and the United States should be cautious in their actions.
"If both sides fail to make such necessary concessions, then not only will the two countries, but the whole region and the whole world end up paying a heavy price for a possible confrontation," it wrote.
Japanese Prime Minister Shinzo Abe the the missile test-fire was "absolutely unacceptable" and a "grave threat to our country."
Abe, speaking during an official visit to Britain, called upon the international community and China in particular, to "show solidarity" in responding to North Korea.
The launch came hours after U.S. Secretary of State Rex Tillerson told the United Nations that the threat of a North Korean nuclear strike on Seoul or Tokyo "is real" and that any failure to act may bring "catastrophic consequences."
In a speech to the UN Security Council on April 28, Tillerson called on UN members to strengthen financial sanctions against North Korea or downgrade their diplomatic relations with Pyongyang in response to the regime's nuclear and ballistic-weapons programs.
He said North Korea has undertaken a "dangerous" course of action for years and that it is time for "us to retake control of the situation."
"For the past 20 years, well-intentioned diplomatic efforts to halt these [weapons] programs have failed," Tillerson told the Security Council.
"In light of the growing threat, the time has come for all of us to put new pressure on North Korea to abandon its dangerous path," he said.
Tillerson called on UN members to live up to their commitments related to sanctions against North Korea, as well as to increase the country's financial isolation by imposing new sanctions and tightening those already in place.
He said diplomatic efforts are preferred, but he also expressed the willingness of the United States to take military action, if necessary, to counter North Korean aggression.
All options to respond to "further provocations must remain on the table," Tillerson said.
The U.S. secretary of state also called on China, Pyongyang’s main ally, to assist in efforts to keep North Korea’s weapons program in check, saying, "We look forward to further actions to what China has already done."
On April 27, Tillerson said that China had threatened to impose sanctions on North Korea if it conducts further nuclear tests.
He said China was "in communication with the regime in Pyongyang" and had "confirmed to us that they had requested the regime conduct no further nuclear tests."
Tillerson said Beijing also told Washington it had informed North Korea that "if they did conduct further nuclear tests, China would be taking sanctions actions on their own."
But Chinese Foreign Minister Wang Yi said at the UN meeting on April 28 that "the key to solving the nuclear issue on the peninsula does not lie in the hands of the Chinese side."
The North Korean missile test also comes as the USS Carl Vinson aircraft carrier group arrived near the Korean Peninsula, where it joined a U.S. submarine, the USS Michigan, which is docked in a South Korean port.
North Korea's official newspaper of the country's ruling Workers Party, the Rodong Sinmun, said the arrival of the aircraft carrier group was a "reckless action of the war maniacs aimed at an extremely dangerous nuclear war."
The paper's commentary included a threat that intercontinental ballistic rockets will "fly into the United States if [Washington]...shows any slight sign of provocation."
The USS Carl Vinson had just completed an exercise with the Japanese Navy in the channel between North Korea and Japan.
Pyongyang's nuclear and ballistic missile programs have been banned by the United Nations.
Tensions have risen on the Korean Peninsula with harsh words between Trump and North Korean leader Kim Jong Un.
Russian Deputy Foreign Minister Gennady Gatilov said after Tillerson's speech on April 28 that increased rhetoric and "reckless muscle-flexing" regarding North Korea could lead to missteps and "frightening consequences."
In a briefing with U.S. senators on April 26, senior officials in Trump's administration said their goal was to push North Korea into dismantling its weapons programs through tougher international sanctions and diplomatic pressure.