Trucks transport goods to North Korea through the Friendship Bridge linking China and North Korea on Sept. 5. (Minoru Iwasaki/AP)

President Trump renewed a threat Thursday to use military force against North Korea and raised doubts about whether negotiations could succeed in resolving the brewing crisis over Pyongyang’s nuclear weapons.

“Military action would certainly be an option. Is it inevitable? Nothing’s inevitable,” Trump said during a news conference. “It would be great if something else could be worked out. We would have to look at all of the details, all of the facts.”

U.S. officials said an offer to negotiate with North Korea remains on the table, but Trump has repeatedly discounted the value of beginning another effort to talk North Korea out of its arsenal.

All previous efforts have failed, and North Korea now possesses both a stockpile of weapons and missiles capable of threatening U.S. shores.

“We’ve had presidents for 25 years now, they’ve been talking, talking, talking, and the day after an agreement is reached, new work begins in North Korea” on its rogue nuclear weapons program, Trump said. “So I would prefer not going the route of the military, but it’s something certainly that could happen.”

The United States is seeking the toughest-yet U.N. sanctions against North Korea in response to its latest nuclear test, according to a draft resolution circulated Wednesday. The sanctions would stop all oil and natural gas exports and freeze the government’s foreign financial assets.

North Korea greeted the proposal with a threat. “We will respond to the barbaric plotting around sanctions and pressure by the United States with powerful counter measures of our own,” read a statement delivered at an Asian economic summit in Russia on Thursday.

Chinese Foreign Minister Wang Yi said Thursday that Beijing would support further U.N.-imposed “measures” against North Korea following its latest nuclear test Sunday but stopped short of saying whether China would back crippling economic sanctions such as a halt to fuel shipments.

Trump has put a priority on pressuring China to “do more” on North Korea. After Sunday’s nuclear test, he tweeted that Pyongyang has become a “threat and embarrassment to China”— a critique of Chinese President Xi Jinping.

China — the main economic lifeline for North Korea — has long been hesitant to completely cut off the crude oil supply to North Korea, worried that economic instability could bring a flood of refugees to the Chinese border and the potential fall of its ally North Korea to U.S. ally South Korea.

“Given the new developments on the Korean Peninsula, China agrees that the U.N. Security Council should respond further by taking necessary measures,” Wang, the foreign minister, told reporters. “We believe that sanctions and pressure are only half of the key to resolving the issue. The other half is dialogue and negotiation.”

Trump did not address sanctions as he spoke at the White House, where he appeared alongside Sheikh Sabah Ahmed al-Sabah, the visiting Kuwait ruler.

Trump did not rule out an eventual U.S. strategy of containing North Korea’s nuclear weapons instead of eradicating them, saying he will not bargain with North Korea in public.

“I don’t put my negotiations on the table, unlike past administrations. I don’t talk about them,” he said. “But I can tell you that North Korea’s behaving badly and it’s got to stop, Okay?”

A U.S. official who briefed reporters later Thursday suggested that Trump is merely being careful and has not backed off the demand that North Korea give up its nuclear weapons. That demand has been a mainstay of U.S. policy for more than a decade and was the basis for extensive negotiations under former president George W. Bush, which ultimately failed.

“The president likes to keep his cards close to his chest, especially on matters of national security,” the senior administration official said.

“I wouldn’t read too much into the absence of an assertion” that North Korea must renounce its nuclear weapons, said the official, who requested anonymity to discuss some aspects of the evolving U.S. policy toward North Korea.

The kind of nuclear deterrence policy that the United States adopted toward the former Soviet Union would probably not work with North Korea, the official said. That policy relied on each nation’s interest in self-preservation to prevent either from launching a first strike.

“We are very concerned that North Korea might not be able to be deterred, that there are real differences between North Korea and the small, small group of nations that have these weapons,” the official said.

The official said the United States is worried about a rising threat of “miscalculation” by North Korea, which may think the warnings of U.S. force are hollow. That partly explains the recent emphasis by Trump, Defense Secretary Jim Mattis and others on the overwhelming strength of U.S. military capabilities.

“Our military has never been stronger,” Trump said Thursday. “Each day, new equipment is delivered; new and beautiful equipment, the best in the world — the best anywhere in the world, by far.”

“Hopefully, we’re not going to have to use it on North Korea. If we do use it on North Korea, it will be a very sad day for North Korea.”

Secretary of State Rex Tillerson has also invited negotiations under the right circumstances. Last month, he sought to reassure North Korean leader Kim Jong Un that the United States does not want to oust him or invade his country.

State Department spokeswoman Heather Nauert insisted the strategy of applying diplomatic pressure on North Korea, while slow going, is effective. Several countries, including Spain, Peru and Kuwait, she said, have set numerical limits on guest workers and Pyongyang’s diplomats.

“It will take time to help remove that money that the DPRK is getting, and which we believe is going to illegal nuclear and ballistic missile programs,” she said, using the abbreviation for North Korea’s formal name, the Democratic People’s Republic of Korea.

The threat of force and the offer of negotiations can coexist, U.S. officials said.

“We’ve left the door open to talks with the North Koreans from the earliest days of this administration,” said an official, noting that Pyongyang has responded with ballistic missile tests, Sunday’s test of what it claims was a hydrogen bomb and other provocations. “Their actions have spoken louder than words. It’s just not the time to negotiate with North Korea. That’s plainly clear to us.”

Rauhala reported from Beijing. Carol Morello in Washington and Luna Lin in Beijing contributed to this report.

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