An international consensus that includes China has now emerged that North Korea's "threatening behavior" cannot go on, the US national security adviser said Sunday.
Speaking after North Korea's latest missile test, which US officials called a failure, H.R. McMaster said, "I think there's an international consensus now, including -- including the Chinese and the Chinese leadership -- that this is a situation that just can't continue."
Amid sharply heightened tension over North Korea's nuclear and missile programs, McMaster said the US and allies were studying all actions "short of a military option," though the Trump administration has taken pains never to completely rule that out.
Vice President Mike Pence, who arrived in Seoul on Sunday, assailed the missile test as a "provocation" and assured South Korea of Washington's full support against the threat from its volatile neighbor. Pence is in Seoul for talks on curbing the North's weapons programs amid fears that it is planning another nuclear test.
"This morning's provocation from the North is just the latest reminder of the risks each one of you face each and every day in the defense of the freedom of the people of South Korea and the defense of America in this part of the world," Pence told US military families at an Easter dinner, at the start of a 10-day Asia tour.
Some 28,500 US troops are stationed in the South.
Trump has ordered a naval strike group, led by aircraft carrier Carl Vinson, to the region as a deterrent against threatening North Korean behavior.
McMaster, speaking to ABC from the Afghan capital of Kabul, repeatedly stated that China -- North Korea's key ally -- is increasingly concerned about the reclusive communist state's behavior.
The new consensus is "that this problem is coming to a head. And so it's time for us to undertake all actions we can, short of a military option, to try to resolve this peacefully," McMaster said.
McMaster said President Donald Trump has made clear he will not allow the nuclear-armed Pyongyang regime to put the US and its regional allies, led by South Korea and Japan, under threat.
Trump turned to Twitter over the weekend to underscore the importance of cooperation with China on the Korean problem.
Having blasted Beijing throughout his presidential campaign for unfairly manipulating its currency, he tweeted Sunday: "Why would I call China a currency manipulator when they are working with us on the North Korean problem? We will see what happens!"
McMaster told ABC that Trump had directed US military, diplomatic and intelligence officials to provide him with options -- in concertation with regional allies including China -- that could be used "if the North Korea regime refuses to denuclearize."
He called North Korean leader Kim Jong-Un "a threat to all people in the region, and globally as well," but cautioned that Trump "is clearly comfortable making tough decisions."
A White House foreign policy adviser, briefing reporters on the plane that carried Pence to Seoul, was asked what steps China had committed to when President Xi Jinping met recently with Trump in Florida.
"There were a number of steps that were discussed," the briefer said, adding that when China recently turned back ships bringing North Korean coal, it was a "good first step."
"China is the key," Senator John McCain, chairman of the Armed Services Committee, said Sunday on NBC. "They can stop this if they want to because of their control over the North Korean economy."
But he cautioned that the risks in dealing with a deeply unpredictable North Korean regime were high. "This could be the first real test of the Trump presidency," McCain said.
The latest missile launch came a day after a defiant North Korea staged a massive military parade in Pyongyang, showcasing nearly 60 missiles -- including a suspected new intercontinental ballistic missile.
But the missile involved in the failed test evidently was smaller. The briefer on Pence's plane called it "a medium-range missile."
"The missile blew up almost immediately," the US Defense Department said of the early-morning launch from the North's east coast.
US Defense Secretary Jim Mattis said Trump was aware of the failed test but had "no further comment."
North Korea has often test-fired missiles to mark major dates such as Saturday's 105th anniversary of the birth of the nation's founder Kim Il-Sung, or as gestures of defiance when top US officials visit the region.
South Korea's foreign ministry said that by conducting the latest test just a day after displaying a series of missiles, "North Korea has threatened the whole world."