Russian foreign minister Sergei Lavrov said Moscow is ready for direct talks even as North and South Korean officials continued to reach out to each other over the next month's Pyeongchang Winter Olympics.
Russia, a long-time of ally of Kim's regime, has consistently opposed US sanctions on North Korea even as Trump requested the Putin-led government to stop oil imports to the country.
Last month, two senior European security experts had said Russian tankers supplied fuel to North Korea on at least three occasions in recent months by transferring cargoes at sea, Reuters had reported.
Russia's foreign ministry and the Russian customs service both refused to comment on the oil supply to North Korea.
The US State Department, in a statement, called on Russia and other UN members to "strictly implement" sanctions on North Korea and to work "more closely together to shut down UN-prohibited activities, including ship-to-ship transfers of refined petroleum and the transport of coal from North Korea."
Meanwhile, North Korea is also planning to send a large delegation to the Winter Olympics in addition to the athletes and performance group.
Media reports said South Korea is seeking to form a united women's ice hockey team for the Winter Olympics, although it hasn't been confirmed.