Over 40 nations have accused North Korea of breaching U.N. sanctions on refined petroleum imports, according to a report submitted to the Security Council that was seen by Reuters. North Korea is currently restricted to an import limit of 500,000 barrels of refined petroleum products a year.

A reported 43 nations, including the U.S., U.K. and France, told the Security Council sanctions committee that 1.6 million barrels of refined petroleum had been imported by North Korea in the first five months of the year. The imports were conducted by illicit ship-to-ship deliveries at sea “on a regular basis as the [Democratic People’s Republic of Korea] primary means of importing refined petroleum,” the complaint reads.

These countries urged the Security Council sanctions committee to determine if the limit had been surpassed and “inform member states that they must immediately cease selling, supplying or transferring refined petroleum products to the DPRK for the remainder of the year.”

The complaint says that Russia and China have been the main nations delivering refined petroleum to North Korea. Russia and China have previously attempted to block the Security Council sanctions committee from declaring that North Korea breached its petroleum import limit.

The 15-member Security Council has implemented numerous sanctions on Pyongyang due to its nuclear weapons program and ballistic missiles, banning the trade of arms and military equipment with the isolated Asian nation. The U.S. has also unilaterally implemented sanctions on North Korea, targeting North Korean financial transactions and labor networks.

Pyongyang continues to expand its nuclear arsenal, despite international condemnation. According to a June report from the Stockholm International Peace Research Institute, North Korea added up to 20 more nuclear warheads in 2019, with the country having a total of 30 to 40 warheads.