German gas importer Uniper does not rule out that Germany will eventually consider gas rationing after Russia's decision to suspend gas flows through the Nord Stream 1 gas pipeline indefinitely.

The company, Germany's largest importer of Russian gas, is also considering legal action against Moscow-based giant Gazprom to compensate shareholders for a 90 percent drop in their market value following a sharp drop in Russian gas supplies since June.

Gas prices in Europe rose on Monday after Russia stopped pumping through Nord Stream 1, the main supply route to the continent.