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European Union Regulation number 994/2010, passed in 2010 to safeguard gas supplies, could include banning gas companies from selling LNG tankers outside of Europe, keeping more gas in reserve, and ordering industry to stop using gas.
European Energy Commissioner Guenther Oettinger said last week during negotiations with Ukraine and Russia that the bloc was preparing a "Plan B" to protect gas supplies in the worst case scenario.
Hungary, likely to be among the countries most affected by a cut in supplies, said it was monitoring the need for further increases in strategic reserves. The Development Ministry told Reuters it was also looking at "potential regulatory methods that would prompt market players to build reserves beyond the regulatory minimum."
Cutting industrial consumption would hurt an already shaky European economy, while banning utilities from selling liquefied natural gas (LNG) tanker cargoes overseas would hurt their revenues.
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European utilities have been preparing for a supply cut by injecting as much gas as possible into storage and as a result, the region's storage facilities are filled to 90 percent, or 70 billion cubic meters (bcm), equivalent to 15 percent of Europe's annual demand.
Whatever the bloc does, it will struggle to compensate fully if Russian gas stops coming to Europe, political and industry sources say. Gas prices have risen 35 percent since July due to this threat.
Limited alternatives
Russia meets around a third of EU demand for oil, coal and natural gas, according to EU data. In return it receives some $250 billion a year, or around two-thirds of government revenue.
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Europe drafts emergency energy plan