Prague  - The European Union Saturday threatened to bypass Russia and Ukraine for the bloc's gas needs if irregularities in Russian gas supplies via Ukraine persist in the future, Czech officials said.

Czech Vice-Premier for European Affairs Alexandr Vondra said the EU was ready to speed up work on Nord Stream and South Stream pipelines that would bring Russian gas to Europe without passing through Ukraine.

The 27-member bloc would also give a boost to plans for the Nabucco gas pipeline that would bring Caspian gas to the EU, he said. The Czech Republic chairs the EU for a half year since Thursday.

"If this goes on for too long the EU has ways to avoid Russia as a supplier and Ukraine as a (transit country). This is our message to them," said Czech Republic's energy security envoy Vaclav Bartuska.

However, those pipelines are planned to be completed in several years. Bartuska declined to say how the EU would hurry construction. "If problems continue it could be fast," he said.

The EU, which strongly urged the two countries to resume negotiations, planned to summon an urgent meeting on the subject in Brussels on Monday and dispatch an expert mission to both countries later next week, Vondra said.

Czech officials spoke to reporters after meeting Gazprom's export chief Alexander Medvedev, who assured them that Gazprom will meet its obligations to EU customers.

However, Medvedev told reporters earlier Saturday that Russia's gas export monopoly had limited capacities to compensate EU customers for gas allegedly stolen by Ukraine.

The Russian-Ukrainian row over a new supply contract and alleged unpaid bills escalated on Thursday when Gazprom cut supplies to Ukraine. The EU began to feel the pinch Friday as pressure began to drop in gas pipelines on the EU border.

Vondra said there were no reasons for immediate concerns as gas storage tanks across Central Europe were full.

Medvedev accused Ukraine of stealing more than 35 million cubic metres of gas per day since Friday from export pipelines as well as from underground storage tanks. Ukraine has denied such claims.

The EU had no access to real data from Russia and Ukraine concerning gas flows, Bartuska said. The bloc now planned to set up more measuring stations along the route, to which Gazprom agreed, Vondra said.

Ukraine as well as Russia appealed to the EU to get involved in the dispute but the bloc has so far resisted those calls.

Ukraine asked the EU to broker the deal, while Gazprom's Medvedev urged the bloc Friday to punish Ukraine for hampering gas transit to Europe.

He said it was up to the EU to act against Ukraine by obliging it to comply with bloc's energy charter, which Kiev joined. Russia did not sign the pact.

"We refuse to be participants or arbiters of this dispute, which we consider to be a commercial one," Vondra said. (dpa)