• Russia demands 'unfriendly' countries to pay for gas in roubles
• Russia has threatened to cut off gas unless the demand is met
• Kremlin says Gazprom is working on the scheme
• Only a few have agreed on the gas-for-roubles scheme
Russian energy giant Gazprom (GAZP.MM) has told Poland and Bulgaria it will halt gas supplies from Wednesday, in a major escalation of Russia's broader row with the West over its invasion of Ukraine.