Reuters says Russian tankers also fueled North Korea via transfers at sea.

Citing two senior Western European security sources, the report said Saturday that Russian tankers supplied fuel to North Korea on at least three occasions in recent months by transferring cargoes at sea, providing an economic lifeline to the secretive Communist state.

The sources said that sales of oil or oil products from Russia, a veto-wielding member of the UN Security Council, breach UN sanctions.

One security source, speaking on condition of anonymity, told Reuters that Russian vessels have made ship-to-ship transfers of petrochemicals to North Korean vessels on several occasions this year in breach of sanctions.

Another source, who independently confirmed the existence of the Russian ship-to-ship fuel trade with North Korea, however, said there was no evidence of Russian state involvement in the latest transfers.

Backing their claims, the two security sources cited naval intelligence and satellite imagery of the vessels operating out of Russian Far Eastern ports on the Pacific.

Reuters said the transfers in October and November indicate that smuggling from Russia to North Korea has evolved to loading cargoes at sea since it reported in September that North Korean ships were sailing directly from Russia to their homeland.