The United States on Thursday sanctioned two Chinese shipping companies for helping North Korea evade sanctions, demonstrating its resolve to keep pressure on the regime until it dismantles its nuclear weapons program.

The Department of the Treasury said it is sanctioning Dalian Haibo International Freight Co. Ltd. and Liaoning Danxing International Forwarding Co. Ltd. It also said it is updating its advisory on North Korea's illicit shipping practices to name dozens more vessels suspected of exporting North Korean coal or engaging in ship-to-ship transfers of refined petroleum.

The measures follow the collapse of last month's second summit in Vietnam between President Donald Trump and North Korean leader Kim Jong-un.

The two sides failed to reach any accord due to disagreements over the scope of North Korea's denuclearization and sanctions relief from the U.S.

"The United States and our like-minded partners remain committed to achieving the final, fully verified denuclearization of North Korea," Treasury Secretary Steven Mnuchin said in a statement, adding that the full implementation of U.N. Security Council sanctions on North Korea is "crucial to a successful outcome."

The U.N. sanctions, which were imposed in the wake of North Korea's nuclear weapons and ballistic missile tests through 2017, include a cap on the regime's imports of refined petroleum and a ban on its exports of coal.