BRUSSELS- The EU said on Thursday buyers of Russian gas could avoid breaching sanctions if they declare purchases complete when they have paid in euros or dollars, but there may be no workaround if Moscow insists they also use a rouble account for the transaction.

Russian gas giant Gazprom cut supplies to Poland and Bulgaria on Wednesday for refusing to pay for gas in roubles, Moscow's toughest response yet to sanctions imposed by the West over the conflict in Ukraine.

(Reporting by Kate Abnett, Francesco Guarascio and John Chalmers; editing by John Stonestreet)