Russia is trying to hit back against western sanctions.
Europe's energy crisis was caused by the halving of the capacity of theNord Stream 1 line to Germany.
Since the beginning of June, the TTF Dutch natural gas futures have increased in value by 129%.
"European gas prices are soaring again, approaching record highs, as a result of Nord Stream 1 flows falling to just 20% of capacity due to ongoing maintenance," said an analyst. Prices will go up even more if Russian flows stop completely.
Europe gets its natural gas from a number of different sources.
There are gas fields in the North Sea, as well as in northern Africa.
Liquefied natural gas is also imported by ship by many European countries.
The European Network of Transmission System Operators for Gas says Russia has the ability to ship gas to Germany at a rate of 1.76 million hours a day. The Yamal-Europe line that runs from Western Siberia to Germany is a key route.
Efforts have been made to reduce the European Union's dependence on Russian gas. The Trans-Anatolian and Trans Adriatic were finished in the last two years of the 20th century.
The territory of Norway and the UK are where the EU imports gas. France, Germany, the Netherlands, and Ireland all have gas networks.
Italy and Spain both import gas from Algeria.