The U.S. State Department has called on UN member nations to immediately end all sales of refined petroleum to North Korea.

Department spokeswoman Heather Nauert issued the call in a statement Friday and welcomed a decision by the UN committee on North Korea sanctions to deflag and ban port entry of three vessels suspected of engaging in illicit activities with the North.

Nauert said that "North Korea's illicit imports of refined petroleum have substantially breached the UN sanctions cap on refined petroleum by making illicit transfers."

She called on the UN committee to formally recognize this breach and stressed the U.S. will sanction any individual, organization or vessel that aides North Korea's illegal activities. 

She said the U.S. remains committed to achieving the final, fully verified denuclearization of North Korea and the full enforcement of related UN Security Council resolutions is crucial to a successful outcome. 

The spokeswoman said the international community must continue to enforce and implement UNSC resolutions until Pyongyang denuclearizes.

She added the U.S. has deployed aircraft and surface vessels to detect and disrupt the illicit maritime activities. 

The three newly sanctioned oil tankers, two Panamanian and one North Korean, are accused of carrying out banned ship-to-ship transfers of refined petroleum to North Korean vessels.