President Donald Trump reacted to reports that the Chinese were selling oil to North Korea, despite a United Nations resolution to sanction the rogue nation.

“Caught RED HANDED,” Trump wrote on Twitter. “Very disappointed that China is allowing oil to go into North Korea. There will never be a friendly solution to the North Korea problem if this continues to happen!”

Trump was referring to a story from South Korea’s Chosun Ilbo, reporting that United States satellites spotted 30 different illegal transactions of Chinese oil vessels transferring oil to North Korea.

Caught RED HANDED – very disappointed that China is allowing oil to go into North Korea. There will never be a friendly solution to the North Korea problem if this continues to happen! — Donald J. Trump (@realDonaldTrump) December 28, 2017

All 15 members of the Security Council, including Russia and China, voted for the latest sanctioning resolution in December, which banned ship-to-ship transfers.