Over the blue waters of the East China Sea, a Canadian air force patrol crew scans the horizon, searching for vessels suspected of making illicit transfers of oil to North Korea.
The 20-member crew aboard the Aurora CP-140 is on the front line of a U.S.-led multinational effort to enforce United Nations sanctions that cap North Korea's oil imports.
On this clear day in mid-October, the Canadian plane is patrolling international waters off the coast of China — a hotspot, the crew says, for ships attempting to dodge sanctions.
When they locate a suspicious vessel, the crew swoops low, circling to snap pictures from multiple angles. The idea is to "make our presence known," said Major Doug Publicover, the commander of the Canadian mission.
The Canadians pass the information to the Enforcement Coordination Cell, or ECC, a loose configuration of 11 nations that conduct surveillance and share intelligence on North Korea's sanctions violations.
"It's a small piece of the pie," Publicover said of Canada's contribution, "but each country does their bit, and hopefully that deterrence can be larger."
Sanctions under strain
Since 2006, U.N. Security Council sanctions have restricted much of North Korea's economic activity as punishment for its nuclear and missile programs. The sanctions limit North Korea's annual imports to 4 million barrels of crude oil and 500,000 barrels of refined products.
U.S. officials, however, say North Korea regularly exceeds these limits, mainly because of a lack of enforcement by China and Russia — North Korea's key allies. Both countries deny those claims but have taken steps to blunt the impact of the sanctions, which they say are no longer necessary.
Earlier this year, Russia vetoed the renewal of a U.N. panel that monitored sanctions violations. China abstained from the vote. As an alternative, the U.S. and its allies this week created the Multilateral Sanctions Monitoring Team, or MSMT, which aims to fill the intelligence gap left by the disbanded panel.
"We just collect information, we tabulate it, and we push it off," says Royal Canadian Air Force Commander Larry Moraal, the ECC's deputy director. "[But] they'll have greater access to the international community than we do."
China pushback
As the U.S. and its allies move ahead with sanctions enforcement, China has voiced growing frustration, particularly with patrols near its borders. Chinese military jets have frequently intercepted Canadian and Australian planes on these missions, at times creating tense encounters.
During this week's flight, with VOA aboard, Chinese fighter jets shadowed the Canadian plane for hours as it patrolled the East China Sea. Unlike past incidents, though, the interactions were not dangerous, said Publicover.
"We're in their backyard — we expect to have some company," Publicover said.
China's biggest concern is that some flights "have been seriously approaching or even entered China's airspace," said Hu Bo, director of the Beijing-based South China Sea Strategic Situation Probing Initiative.
In 2023, China accused a Canadian CP-140 of entering its airspace near the disputed Diaoyu Islands, known as the Senkaku Islands in Japan. The islands are administered by Japan but also claimed by China and Taiwan.
When asked by VOA, Canadian officials declined to comment on the incident, underscoring that all its operations occur in international waters.
Philip Shetler-Jones, a senior research fellow at the London-based Royal United Services Institute, said it's easy to understand why China doesn't like patrols so close to its borders.
"I don't think many countries would like it. But that's different from having an acceptable legal basis to say it's not OK — or an acceptable legal basis on which to justify the kind of dangerous maneuvers and actions they've carried out," he said.
Going it alone
With China and Russia increasingly disengaged from enforcing sanctions, U.S.-led mechanisms like the ECC and MSMT are among the few remaining options. Some experts, however, question how effective this approach can be.
"There's no way the U.S. and its allies on their own could enforce U.N. sanctions" without help from China and Russia, says Peter Ward, a research fellow at the Seoul-based Sejong Institute.
Still, Ward said the newly created MSMT can serve as a useful tool for naming and shaming violators, applying pressure, and helping countries struggling to implement sanctions.
Maya Ungar, a U.N. analyst at the International Crisis Group, added that the body could boost its credibility by involving a wider range of countries. But, she said, its accusations will likely carry less weight than those from the now-dismantled U.N. panel of experts.
How to measure success
Despite enforcement efforts, North Korea continues to secure energy imports, often exceeding U.N.-imposed limits. Commander Moraal acknowledges this but said the ECC is raising the cost of sanctions evasion.
As an example, Moraal cites two North Korean-linked coal ships seized by South Korea earlier this year after ECC provided intelligence.
But if the ultimate goal is to curb North Korea's nuclear weapons program, the results appear less encouraging. Recent estimates suggest North Korea now has enough fissile material to build up to 90 nuclear warheads, and it regularly unveils new advanced missile systems.
Ward believes a shift in strategy may eventually be necessary. "At some point, we may need to reckon with the fact that North Korea does have nuclear weapons and figure out how to deal with that," he said.
Still, even if full enforcement is impossible, Ward argues there's a case for maintaining sanctions. "The alternative could reward bad behavior," he said.
"So long as North Korea sanctions remain relatively comprehensive, if very leaky, there are many countries that will see the case of North Korea as a cautionary lesson," he said.
