European natural gas futures jumped as traders weighed the risk of fresh international sanctions against top supplier Russia should it invade Ukraine. 

U.S. President Joe Biden is due to hold a summit with Russian President Vladimir Putin later on Tuesday to warn Moscow against entering its neighbor or risk severe economic penalties, including banking sanctions. Dutch front-month gas jumped as much as 7.6% as energy is central to Russia’s influence abroad. 

The increased tension adds to existing worries over Russian supplies to the European Union, which has already been sharply curtailed in recent months. Global competition for the fuel increased further after Royal Dutch Shell Plc canceled several liquefied natural gas shipments because of an outage in Australia. 

“EU consumers are not getting any break from punitive gas prices,” said Ole Hansen, head of commodity strategy at Saxo Bank A/S. “The market is once again caught up in geopolitical developments with Ukraine border worries raising the prospect for more sanctions on Russia.”

Dutch gas traded as high as 96.75 euros a megawatt-hour by 10:44 a.m. in Amsterdam, while the U.K. month-ahead contract gained 7.1% to 246.51 pence a therm. Prices have retreated from October records, but analysts and traders expect futures to remain high through the winter as the continent’s gas inventories are at their lowest in more than a decade. 

Storage sites are only 66% full, compared with a five-year average of 82% for this time of year. 

Continued Russian aggression could reshape the fate of the completed but not yet operational Nord Stream 2 pipeline to Germany, which the Biden administration hasn’t tried to stop even though it opposes the project. Still, the link faces delays anyway after Germany paused the approval process for the pipeline last month until its owner restructures its operations. 

Prices are also supported by colder revisions in weather forecasts for western Europe, as well as freezing temperatures in Russia, according to consultant Engie EnergyScan.