The request was prompted by a trading error by one of France’s regional energy providers, which accidentally oversold huge amounts of electricity over two days. The unusual alert added to energy pressures across Europe as the region grapples with its worst electricity crisis in decades due to rising costs stemming from reduced gas flows from Russia. It also highlighted severe strains on France’s electricity grid, which is grappling with an unprecedented number of outages at its nuclear reactors – the linchpin of its generation system. French network operator RTE said on Tuesday it sent out the call to neighboring countries to prepare to export more power overnight. The UK’s National Grid and a person close to Spain’s electricity grid confirmed their countries had received the alert. Électricité de Strasbourg – which supplies electricity to the region around the eastern French city and is majority-owned by state-backed utility EDF – said in a statement it was investigating the “dysfunction”. It said it had mis-sold 2.03 gigawatts and 5.75 GW of electricity in two separate transactions on September 6 and 7, and later added that the incident cost it €60 million after it rebalanced its supply needs. Filings with RTE describe the issue as an IT incident. Such requests for emergency assistance are rare. Grid operators typically dispatch no more than a few a year, acting when they see the risk of supply falling short of demand, according to energy companies and grid officials. Energy companies are, however, nervous about possible disruptions to intra-European electricity and gas trade if the region is hit by shortages this winter. The French alert was sent after end-of-day balancing work showed there could be a power shortfall at Électricité de Strasbourg, a person familiar with the matter said. EDF declined to comment. Alerts are sent through the European Alert System — which network operators use to share information — and are used to ensure supplies can be mobilized from elsewhere. In the French case this week, the extra supplies were ultimately not needed, RTE said. Energy providers are constantly entering into transactions to match supply with demand. But the sums at stake are unusually large – one gigawatt alone is equivalent to the capacity of some nuclear reactors, or enough to power a small city for about a year. France was already turning to neighbors for extra electricity on a regular basis because of its reduced nuclear supply, notably the UK — which has been a net exporter of electricity via undersea cables — as well as Germany and Spain. But at the same time Paris is at loggerheads with Berlin and Madrid over a proposed new natural gas pipeline from Spain to France. Olaf Scholz, the German chancellor, and Pedro Sánchez, the prime minister of Spain, support the MidCat pipeline, arguing that it will help reduce energy shortages across the Iberian Peninsula. However, Emmanuel Macron, the president of France, is opposed to the project, saying that existing gas connections between France and Spain are not being fully used. A pipeline that would take several years to complete would not correct short-term stresses and push Europe further into fossil fuel dependence, he added. “I don’t understand the short-term problem we’re trying to solve [with this]Macron said. The French government is stepping up pressure on nuclear fleet operator EDF to fix outages by winter after unexpected corrosion problems at some reactors added to planned maintenance outages and plunged output to multi-decade lows. At a meeting on Friday to tackle the gas price crisis, EU energy ministers in Brussels signaled their support for a temporary cap on the price of gas imports, including from Russia, and an unexpected levy on energy producers.