China’s government is cracking down on its domestic fleet fishing in North Korean waters illegally, and working to prevent sales of North Korean seafood in China.

All Chinese fishing vessels approaching North Korean waters are now required to carry automatic identification systems, and Chinese authorities have stepped up inspections in order to ensure adherence to the rule, according to Daily NK, citing an anonymous source.

Chinese fishing vessels are being asked to provide information regarding their fishing locations, and if they were found to be fishing in North Korean waters, they face large fines and the confiscation of their catch.

Chinese vessels have fished with impunity in North Korean waters for years, and over the past 20 years, an informal system has arisen to allow Chinese vessels to pay a fee to access North Korean waters. North Korea is prohibited from supplying, selling, or transferring seafood or fishing rights to other countries, according to the U.N.’s official outline of sanctions against North Korea, which were put in place to prevent the country from developing nuclear weapons. But despite international sanctions, North Korea has in recent years sold fishing rights to Chinese companies, though occasionally running into legal trouble in China, while at the same time condoning its own trawlers fishing in Russian waters illegally.

“This kind of thing has been possible because the Chinese government just looked on, despite knowing full well that fishery operators were openly operating in North Korean waters after purchasing fishing rights from the North Korean authorities,” the Daily DK source said. “However, with [the Chinese authorities] saying they will crack down hard on this activity, fishery operators will have a tough time operating in North Korean waters for the time being.”

Chinese authorities are also taking steps to prohibit the sale of seafood caught in North Korea from being sold in China. Officially, the practice is formally prohibited under United Nations Security Council Resolution 2371, but in reality, has been relatively common for years, according to Daily NK. While the news site’s objectivity has been questioned, the U.N. Security Council Sanctions Committee on North Korea said in an expert panel report published 27 October it is investigating evidence that North Korean seafood has been sold at markets in China.

China has faced increasing international pressure to combat illegal, unreported, and unregulated (IUU) fishing practices that are common among its fleet. It is taking action as a means of showing its adherence to international law, according to Daily NK.