KIEV/MOSCOW, Dec 20 (Reuters) - Russia has offered to pay Ukraine about $3 billion to end a legal row over gas, a source close to talks told Reuters on Friday, in line with the amount proposed in arbitration rulings between Russian Gazprom and Ukrainian Naftogaz.

The legal row had blocked a new deal to supply Russian gas to Ukraine and the rest of Europe. The existing supply agreement expires on Dec. 31. Talks on a new pact have been underway.

Russia’s Energy Ministry and Gazprom did not reply to requests for a comment. Ukraine’s Energy Ministry and Naftogaz declined to comment.