Ukraine's President Viktor Yanukovych is expected to try to secure an agreement for Kiyv to pay a lower price for Russian natural gas during talks with Russian President Vladimir Putin in Moscow on December 18.
Ukraine says the current price of about $430 per 1,000 cubic metres is draining its budget, but it has balked at Moscow's demands for concessions to achieve a reduction.
Russia has, in particular, said it wanted to buy into Ukrainian gas pipelines through which pump much of the Russian gas bound for Europe.
Russia would also like Ukraine to join a customs union comprising Russia, Belarus, and Kazakhstan.
A senior Russian official has said accession to the customs union could allow Ukraine to buy Russian natural gas at a lower price.
Based on reporting by Reuters and Interfax