Russia and Ukraine are debating natural gas contracts after Russian energy company Gazprom sent Kiev a $7 billion bill for unused 2012 gas covered under a take-or-pay contract. Earlier disputes prompted European leaders to look for ways to break the Russian grip on the energy sector as most of their gas from Gazprom runs through Ukrainian pipelines.
Russia's state-run news agency RIA Novosti reports U.S. Special Envoy for International Energy Carlos Pascual, a former ambassador to Ukraine, met with Ukrainian officials to discuss Ukraine's shale potential.
Shell last month signed a contract said to be worth $10 billion to explore shale natural gas reserves in Ukraine.
"Pascual ... said the United States has technologies for ecologically safe production of shale gas and was ready to share its know-how with Ukraine," RIA Novosti reported.
There was no announcement of the meeting from the U.S. State Department. That department last month said Pascual was in charge of U.S. backing of the Southern Corridor, a network of pipelines meant to diversify Europe's gas sector.