The U.S. and its allies reportedly urged United Nations members to present reports on whether they’re complying with UN-imposed sanctions requiring the repatriation of North Korean workers.

According to Bloomberg News on Monday, the U.S. and more than 20 allies including Germany, Britain and Japan wrote a letter to the president of the General Assembly, urging all members to provide final reports on the matter by March 22.

German Ambassador Christoph Heusgen, who chairs the North Korea sanctions committee, said in the letter on behalf of the group of mainly Western countries that the presence of North Korean workers earning income abroad is a "violation of international law."

South Korea reportedly did not take part. 

As part of resolutions passed in 2017, UN member states were required to send back all North Korean laborers by Sunday. The U.S. and its allies appear to have made the call as some countries have failed to provide an interim report on whether they’re meeting those obligations.