MOSCOW, Dec. 4 - If Ukraine fails to honor its obligations on transiting natural gas from Russia to Western Europe, Russia will have to cut gas supply to Ukraine itself, Russian Prime Minister Vladimir Putin said during a televised question and answer session on Thursday.

"We presume that there will be no problems with transiting our energy resources to Western Europe, and we reached such understandings with Ukraine in the past. But if our partners fail to honor these obligations or, as happened in previous years, resort to siphoning our resources from the transit pipeline without our sanction, we will have to cut the supply," he said.