The EU cut off vital funding to a Gaza power plant, forcing it to shut down the last of its generators and darken tens of thousands of Palestinian homes.
The shutdown on Sunday was another blow to the long-suffering residents of the Gaza Strip, where the Islamic group Hamas has been governing, largely under international isolation, since June.
The power plant already cut electricity to large swaths of Gaza last week after Israel closed a fuel crossing into the coastal territory, citing security concerns. Israel reopened the passage on Sunday, but the plant's Israeli fuel supplier said the EU had instructed it not to deliver new supplies because it would not guarantee payment.
"Fuel supplies will resume if and when the European Union or another credible source notifies us that it will guarantee payment for the power station's fuel," Israel's Dor Alon fuel company said in a statement.
Alex de Mauny, a spokeswoman for the EU's executive branch, confirmed the EU would not finance Sunday's fuel payment.
"In light of the security situation, we've decided to take stock of all of our mechanisms and systems, including auditing, monitoring and funding flows," de Mauny said.
Funding would resume by this evening at the latest, she said.
Gazans initially were unfazed by the outages, because power reserves are always so thin that consumers are used to living without electricity for about five hours a day. But as the shortages dragged on for a third straight day, nerves began to wear thin.
European officials were caught off guard by the power shortage, mistakenly believing the plant had enough fuel for another two days, an EU official said. The official spoke on condition of anonymity according to EU regulations.
The government of moderate Palestinian President Mahmoud Abbas, formed in the West Bank after Hamas took over Gaza, charged the Islamic group with responsibility for the power shortage.
The EU ceased payment "because Hamas took over the electric company and started collecting the revenues and taking them to its pocket," Palestinian Information Minister Riad Maliki told reporters at a press conference on Sunday.
Hamas lawmaker Yehia Musa accused Abbas of a "dirty conspiracy" to persuade international donors to cut off electricity to Gaza in an attempt to discredit Hamas.
The Gaza Generating Co cut power to nearly half of Gaza's 1.4 million people on Friday. It shut off the last of its four generators on Sunday.