Ukraine is still not letting Russian natural gas into its pipeline system due to "technical reasons," a spokesman for Ukraine's state gas firm Naftogaz confirmed Thursday.

Ukraine is still not letting Russian natural gas into its pipeline system due to "technical reasons," a spokesman for Ukraine's state gas firm Naftogaz confirmed Thursday.

Russia's state gas firm OAO Gazprom (GAZP.RS) said earlier Thursday that Ukraine for the third day in a row "refused" to open its taps despite requests from Gazprom to transit nearly 100 million cubic meters of natural gas to consumers in Slovakia, Moldavia and Balkan countries, which have been the hardest hit by the gas dispute.

Russia cut off gas supplies to Ukraine on New Year's Day following a dispute over late payments and a failure to agree on a price for 2009.

On Jan. 7, Russia shut off all supplies, accusing Ukraine of stealing gas bound for Europe, a charge Kiev has denied.

Russia agreed to start shipments again Tuesday, after reaching an agreement with Ukraine and the European Union.

But Tuesday morning, Ukraine refused to let gas into its pipeline system, saying Russia sent the gas to the wrong entry point near the border town of Sudzha, making it technically impossible to ship the gas to Europe.

Gazprom insists the gas is delivered through Sudzha, which it says is the sole entry point for European exports. Meanwhile, Naftogaz has asked Gazprom to deliver the gas at two other entry points, Valuiki and Pisarevka.

"This is not only our position. This is also the position of the European Commission," said Naftogaz spokesman Valentin Zemlyansky.

However, European Commission spokesman Ferran Tarradellas said Wednesday it had received information from Ukraine that the gas was delivered through the wrong entry points, but denied this was the European Commission's position.

The dispute has left hundreds of thousands of households in southeastern Europe without heating and has forced factories to shut down production in several production.