The document was sighted by Reuters and Washington submitted it to the Security Council members.
“Our information suggests that between Jan. 1 and May 30 of 2018, DPRK (North Korean) tankers have called in port in the DPRK at least 89 times.
“This is likely to deliver refined petroleum products illicitly procured via STS (ship-to-ship) transfers,’’ the U.S. told the U.N. Security Council’s North Korea sanctions committee.
In December, the 15-member Security Council capped refined petroleum product exports to North Korea at 500,000 barrels a year.
The U.S. accusation of a sanctions breach comes as Washington engages with North Korea in a bid to negotiate to denuclearise the Asian country.