BEIJING—China has tightened restrictions on exports to North Korea of items with potential dual use in weapons of mass destruction and conventional arms.

The ban on exports of potential dual-use items, including software, machinery and chemicals, is in line with U.N. Security Council resolution number 2375, the Chinese Ministry of Commerce said in a statement on its website posted late Sunday. That resolution was passed in September.

The announcement suggests that China is continuing to comply with U.N. sanctions on Pyongyang even after North Korean leader Kim Jong Unpaid a surprise visit to Beijing for his first meeting with Chinese President Xi Jinping last month.

China has accounted for around 90% of North Korea’s foreign trade in recent years, but has stepped up enforcement of U.N. sanctions in the past year in response to Pyongyang’s repeated nuclear bomb and missile tests.

Write to Jeremy Page at jeremy.page@wsj.com