The United States, Japan, and the Republic of Korea (South Korea) issued a trilateral statement on North Korea on Monday, denouncing Pyongyang’s “flagrant disregard for multiple United Nations Security Council resolutions prohibiting its ballistic missile and nuclear programs” and calling for “strong international pressure on the regime.”

The statement cites U.N. Security Council Resolutions 2270 and 2321, which “imposed robust and comprehensive sanctions on North Korea to inhibit its campaign to develop operational nuclear and missile capabilities.” It suggests additional “means to restrict further the revenue sources for North Korea’s weapons programs, particularly illicit activities,” may be called for.

North Korea engages in quite a few “illicit activities” to obtain much-needed hard currency, including the narcotics trade, counterfeiting, and smuggling contraband. Their smuggling operations have handled everything from counterfeit cigarettes and pharmaceuticals to endangered species products.

The ultimate goal of these measures is nothing less than “the complete, verifiable, and irreversible denuclearization of North Korea.”

Representatives from the U.S., Japan, and South Korea also “discussed the violations of human rights in North Korea, and reaffirmed the importance of an early resolution of the abductions issue as well as a resumption of reunions of separated families.”

North Korea has abducted Japanese citizens on a staggering scale since the 1970s. Japan recently estimated there have been 886 victims, demanding Pyongyang return all those who are still alive and provide a full accounting of those who died in captivity. Survivors have told astounding and horrifying stories of their treatment by the North Koreans.

Yonhap News also reports there will be cooperation between the U.S., Japan, and South Korea on a response to the assassination of Kim Jong-nam, half-brother of North Korean dictator Kim Jong-un.

“The representatives of the three countries exchanged views on the killing of Kim Jong-nam in Malaysia and agreed to closely coordinate a response while monitoring the situation,” said South Korean envoy Kim Hong-kyun. “Our side emphasized that Kim Jong-nam’s killing is a serious violation of international norms in that a banned chemical weapon was used, and the international community respond strongly to this in light of the fact that it is an inhumane and anti-human rights crime.”

According to inside sources, the trilateral group was not quite prepared to formally accuse North Korea of masterminding the assassination, which involved a nerve agent classified as a weapon of mass destruction, but “the discussions took place based on the assumption that Pyongyang was behind the killing.” Yonhap reports the U.S. State Department may add North Korea back to the list of terrorism-sponsoring nations, from which it was removed in 2008 as a reward for progress in denuclearization talks.

Increased pressure on North Korea will be difficult to achieve without cooperation from China. Chinese State Councilor Yang Jiechi is currently meeting with American officials in Washington, making the first visit by a senior Chinese official since President Donald Trump took office. North Korea is reportedly a major item on the agenda for Yang’s visit.

Writing at Foreign Policy on Monday, Patricia Kim suggests getting China on board with stronger sanctions against North Korea by explaining how the current status quo is endangering China’s regional interests.

Patricia Kim notes that China can effectively shut down what passes for an economy in North Korea, including the pipelines for illicit cash flow from smuggling and counterfeiting operations. She suggests the Trump administration portray such irritants to Beijing as South Korea’s interest in missile defense, the possibility of damage to South Korea’s lucrative trading relationship with China, Japan’s adoption of a more aggressive military posture, and the possibility of instability across the Pacific Rim as the price of continued indulgence for Kim Jong-un’s psychotic regime.

The Trump administration seems to have decided direct engagement with North Korea is not the way to go, having denied the visas needed for informal talks in New York City. Voice of America News quotes senior fellow Richard Bush of the Brookings Institution dismissing U.S.-North Korea dialogue as pointless since Pyongyang clearly “knows how it needs to change its goals to satisfy the other parties and how to contact the U.S. government to talk about such changes.”

It seems widely understood that China is key to solving the North Korean problem. The great concern is that North Korea might take China’s temperature, realize it has gone a bit too far, and scale back its misbehavior just enough to smooth out Beijing’s cost-benefit analysis.

Even as China’s diplomat arrived in Washington, North Korean Vice Foreign Minister Ri Kil-song was landing in Beijing, to make the first Chinese visit by a high-ranking North Korean official in several months. Chinese media coverage of his visit suggests Beijing is still more incensed by South Korea’s interest in the American THAAD anti-missile system than anything North Korea has done.