In response to the turmoil, the White House sent the president’s global energy coordinator Amos Hochstein to Europe on Tuesday, officials said. He will travel to Paris and Brussels to discuss contingency planning with the US-EU energy group set up in March, a month after Russia invaded Ukraine. “That was our biggest fear,” the US official said. The impact in Europe could backfire in the US, sending gas and electricity prices soaring, the official said. It will also be a major test of European resilience and unity against Russia, as the Kremlin shows no signs of backing down on Ukraine. The US and Brussels have asked EU members to conserve natural gas and store it for the winter, and on Tuesday energy ministers agreed in principle to cut gas use by 15% from August to March. There will also be discussions in the coming days about increasing nuclear power generation across Europe to offset gas shortages, officials said. Germany had planned to completely phase out the use of nuclear power by the end of 2022, but US officials are hoping to persuade Berlin to extend the lives of its three remaining nuclear plants amid the energy crisis, an official said. American officials, who have been in close contact especially with German and French officials on this issue, are extremely concerned that Europe may face severe gas shortages in the winter. This is because EU countries will struggle to fill their reserves in the coming months with Nord Stream 1 providing only a fraction of its capacity. Germany withdrew plans for another Russia-Europe gas pipeline, Nord Stream 2, after Russia invaded Ukraine in February. The US opposed this pipeline, warning that it would only increase European dependence on Russian gas. But Germany argued that the pipeline was a purely commercial project and could serve as an energy bridge as it phased out nuclear and coal. The US eventually issued waivers allowing the pipeline project to proceed without crippling sanctions. Now, officials have said that a 15 percent reduction in natural gas consumption in Europe, along with an increase in global liquefied natural gas exports to Europe, including the U.S., is unlikely to be enough to offset the shortages. “This is an open gas war that Russia is waging against a united Europe,” Ukrainian President Volodymyr Zelensky said on Tuesday. The US official said it was clear the Russians were “hitting” and trying to “destabilize Europe” because they were not achieving their goals in Ukraine. A spokesman for the National Security Council described Russia’s moves as just its latest attempts “to use natural gas as a political and economic weapon.” “Russia’s energy coercion has put pressure on energy markets, raised prices for consumers, and threatened global energy security. These actions only underscore the importance of the work the United States and the European Commission are doing to end our dependence on Russian energy,” the spokesman said. “We will continue to work with our European partners to reduce dependence on Russian energy and support their efforts to prepare for further Russian destabilization of energy markets.”