Rosneft Sends Oil to Hungary, Slovakia with Glencore's Help
Rosneft declined immediate comment.
The company is supplying Urals crude oil via the Druzhba pipeline, the sources said.
Glencore recently became a Rosneft shareholder after it acquired, together with a Qatari fund, 19.5 percent in the Kremlin-controlled producer.
Trading sources told Reuters that Rosneft will supply 80,000 tonnes of oil via the route to each of the countries this month, while supplies will total 500,000 tonnes in January to March.
Urals is being supplied to Hungary's Mol Danube refinery and the Bratislava refinery in Slovakia.
Rosneft has made a foray into new markets after last year acquiring Russian mid-sized oil producer Bashneft, whose assets are predominately located in the mountains of the Urals.
Bashneft previously supplied around 600,000 tonnes of oil a quarter to Hungary and Slovakia via Normeston trading company.
Rosneft has been supplying oil via the Druzhba (Friendship) pipeline to Poland, Germany and the Czech Republic. It has gradually ditched intermediaries, such as Souz Petroleum, Mercuria Energy and Sunimex from the chain of supplies.
Many market observers say Rosneft's deliveries to Hungary and Slovakia via Glencore may be due to obligations it has taken on as part of the deal for Glencore to become a Rosneft shareholder.