SEOUL -- Investigators are in the advanced stages of a probe into a South Korean-flagged oil tanker suspected of illicitly supplying 4,300 tons of petroleum products to North Korea through ship-to-ship transfers, it was learned on Wednesday.
The South Korean Coast Guard have held the P-Pioneer at a port in Busan since October, marking the first time a South Korean-flagged vessel has been detained for suspected violations of a United Nations Security Council sanctions resolution.
The transfer allegedly took place in the East China Sea in September 2017, and involved two North Korean ships.
The news comes a week before the April 11 summit between U.S. President Donald Trump and South Korean President Moon Jae-in in Washington, where the two leaders are expected to discuss efforts to convince Pyongyang to denuclearize.
A tip from U.S. officials initiated the investigation into the P-Pioneer, South Korea's Yonhap News reported. The coast guard turned over the case against the ship's captain and corporate owner to prosecutors on Jan. 30.
A total of four vessels, including foreign ships, are being held under suspicion of committing illegal ship-to-ship transfers and other violations, according to South Korea's foreign ministry. "We are discussing the matter closely with the U.S. and the United Nations Security Council's North Korea Sanctions Committee," a ministry official said.
Experts say North Korea has skirted the web of sanctions imposed by the Security Council in December 2017. Despite an import cap of 500,000 barrels of oil, a report to the sanctions committee noted 148 suspected instances of ship-to-ship transfers between January and August 2018, which would equate to at least 830,000 barrels.
The U.S. and Japan have monitored waters for illicit transfers. South Korea, which has taken a more conciliatory stance toward the North, has been expected to coordinate closely on interdictions.
Local authorities investigated a South Korean-flagged vessel last year, but decided to let the ship go due to lack of evidence, according to a South Korean lawmaker briefed on the case.
The vessel had stopped in the East China Sea 300km north of Taiwan on multiple occasions between May and August of last year. The ship was said to have ferried 160,000 tons of petroleum products over 27 trips since 2017.