The Chinese will “have to” enforce sanctions against the country if the North Korean nuclear issue is ever going to be solved, U.S. National Security Advisor Robert O’Brien said on Wednesday.

The comments come as Washington and Pyongyang remain stuck in a months-long diplomatic stalemate over the North’s nuclear weapons program, and whether U.S. and UN sanctions currently targeting the DPRK should be lifted or expanded.

China is North Korea’s top trading partner by far, and is viewed by many observers as a weak link in a global sanctions regime that was intended to hurt Pyongyang’s economy.

In his comments on Wednesday, O’Brien was explicit about what China should do, from the U.S. perspective, in order to help pressure North Korea into giving up its nuclear weapons.

“This situation with North Korea can’t be solved without the Chinese,” O’Brien said at the Meridian International Center, a non-profit organization in Washington.

“We can’t do it just with the Republic of Korea, just with Japan, just with our friends and allies. We have to have the Russians involved, we have to have the Chinese involved,” he said.

“The Chinese have to enforce the sanctions against North Korea. They’ve got to stop the ship-to-ship transfers. They have to send the labor — the folks who are engaged in labor in China, and then sending remittances back to North Korea to keep the economy going,” he continued. “We need the Chinese to assist us as we pressure the North Koreans to come to the table.”

Ship-to-ship transfers — a maneuver often used by DPRK-linked boats to evade trade sanctions — and overseas North Korean laborers have been highlighted by the UN Security Council (UNSC) as sources of revenue that Pyongyang has allegedly used to build up its weapons program.

Both are banned under UNSC sanctions, and all countries — including China — were supposed to repatriate any North Korean workers in their territory by late December last year.

In January, the U.S. Treasury Department blacklisted two companies — one in Beijing and one in Pyongyang — for helping DPRK nationals work abroad.

China, along with Russia, has recently become more assertive about the sanctions issue.

Beijing and Moscow’s UN representatives introduced a draft resolution in December that called for the removal of all sanctions “related to the livelihood of the civilian population of the DPRK.”

The U.S. State Department rejected that proposal, however, and multiple UN diplomats told NK News at the time that it had no chance of passing.

On Thursday, National Security Advisor O’Brien said that China should want to go along with the U.S. on the sanctions issue — because a nuclear North Korea goes against China’s interests, too.

“Look, we’re farther away from North Korea than the Chinese are,” O’Brien said. “I’m not sure they’re thrilled with the idea of having a nuclear North Korea.”

“So I think it’s in China’s interest to work with us. They have been working with us. And we’ll continue to press them to do everything they can to help Chairman Kim realize the commitment he made in Singapore,” he said.

“Singapore” refers to Trump and Kim’s first meeting, in 2018, when they vaguely committed to the denuclearization of not just North Korea, but the entire Korean peninsula.

“My hope is that North Korea will come back to the table,” O’Brien added.

“We had some good talks with them late in the fall in Scandinavia,” he said, referring to the last face-to-face meeting between the two countries, in October 2019.

“We hope they’ll come back to the table and then come back to Sweden and meet with us. But we’ll have to see,” he said.