Russian Prime Minister Vladimir Putin told European Commission head Jose Manuel Barroso by telephone that Kiev was blocking the transit of Russian gas after Gazprom gave the go-ahead on Tuesday morning to resume pumping gas via Ukraine but no gas got through to Europe.
"Ukraine has been and will be a reliable transit country, and it has not taken a single step to block Russian gas deliveries to the European Union," President Viktor Yushchenko said.
The move to resume gas supplies to Europe was made after Russia, Ukraine and the EU signed a deal on Monday allowing the presence of international monitors at Ukrainian and Russian gas transportation facilities to oversee gas transit.
Valentin Zemlyansky, a spokesman for Ukrainian energy company Naftogaz, cited Russia's "unacceptable transit conditions" as the reason for blocking its natural gas deliveries.
Russia halted gas supplies to Europe last Wednesday accusing Ukraine of tapping transit gas. Moscow cut off gas deliveries to Ukraine on January 1 after the parties failed to agree on Kiev's debt for supplies in 2008 and a price for a 2009 contract.
"Ukraine has not tapped a single cubic meter of gas either in 2009 or 2008," Yushchenko said.
He said Ukraine remained open to talks on gas supplies from Russia and did not owe anything to any Russian company, saying final payments on the country's 2008 gas debt had been made in late December with an advance payment for January supplies.
According to Gazprom, Ukraine still owes $614 million after paying $1.5 billion.