Update(0918ET): Is Europe starting to panic amid cracks in a 'unified European front'? It appears so, based on a press briefing in Brussels by European Commission President Ursula von der Leyen, who said:

"Its' very clear and the request from the Russian side to pay in rubles is a unilateral decision and not according to the contracts," and further "Companies with such contracts should not accede to the Russian demands. This would be a breach of the sanctions so a high risk for the companies."

She also denounced this "as an instrument of blackmail" after the Gazprom suspension of gas to Poland and Bulgaria. "This is unjustified and unacceptable," she said earlier in the day. "And it shows once again the unreliability of Russia as a gas supplier."