Dhaka, May 2 -- Energy ministers from European Union countries hold emergency talks on Monday, as the bloc strives for a united response to Moscow's demand that European buyers pay for Russian gas in roubles or face their supply being cut off.

Russia halted gas supplies to Bulgaria and Poland last week after they refused to meet its demand to effectively pay in roubles, reports Reuters.

Those countries already planned to stop using Russian gas this year and say they can cope with the stoppage, but it has raised fears that other EU countries, including Europe's gas-reliant economic powerhouse Germany, could be next.

It has also threatened to crack the EU's united front against Russia amid disagreement on the right course of action.

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