The United Nations estimates that more than 50,000 North Koreans are labourers in other countries, mainly in Russia and China. This forced labour program is critical for North Korea, as it pulls in between $1.2 billion and $2.3 billion, which is about 20% of the nation’s estimated military budget.

Relations with China, North Korea’s most important partner since the collapse of the Soviet Union, have taken a frosty turn. Beijing has condemned Kim Jong-Un’s nuclear and missile test with increasing severity over the last several years. In a move that surprised analysts, China supported the UN Security Council’s recent sanctions, billed as the “toughest ever.”  Trade between the two countries has suffered. Chinese imports of North Korean coal decreased by 71.6% from last year, and China’s oil exports to North Korea decreased by 99.6% according to a report released by Beijing in October.

Despite frosty relations with China and a growing regimen of international sanctions, North Korea’s economy grew by 3.9% in 2016, its fastest since 1999. Furthermore, Pyongyang still does business with around 80 countries, according to South Korean government figures. This includes trading arms, textiles, and even socialist-style statues. Shunned by Beijing and threatened by sanctions, Kim Jong-Un’s regime has increasingly turned to Russia.

Indeed, a Russian telecommunications company appeared to begin supplying a new internet connection to North Korea last month, providing Pyongyang with a backup to the connection supplied by China. In the meantime, U.S. efforts to attack North Korean internet infrastructure have ramped up. North Korea’s internet is heavily regulated by the regime and is an almost completely closed system. In addition, a new ferry service was launched in May to carry cargo between the eastern Russian port of Vladivostok and North Korea, and Russian state media has announced plans for more rail links between the two nations.

The biggest cash cow for Pyongyang, however, has been forced labour sent to Russia. An estimated 30,000 labourers now work in eastern Russia, mostly as cheap construction workers building apartment buildings, roads, and rail. Their wages are sent to government coffers in North Korea.

To comply with sanctions, Russia’s Minister of Labour and Social Protection Maxim Topilin announced Friday that no work quota would be assigned to North Koreans next year. However, this statement does not address the thousands of people currently forced by their oppressive government to work in the country. If sanctions are to be truly effective, policy makers must find a way to end North Korea’s trade in forced labour.