China's trade with North Korea shrank by more than half last month, as Beijing implements United Nations sanctions against Kim Jong Un's nuclear weapons program.

The value of Chinese goods exported to North Korea last month fell 23 percent year on year, according to data released Friday by China's General Administration of Customs. Imports from the country also plunged 82 percent in December. All told, trade between the two sides fell almost 51 percent during the month.

In 2017 as a whole, China's overall trade with North Korea declined by more than 10 percent to about $5 billion, as U.S. President Donald Trump secured Beijing's backing for four escalating rounds of sanctions. The U.S. sees cutting off North Korea's economic ties with China — the country's dominant trading partner — as essential to forcing Kim back to the negotiating table.