KYIV, Ukraine (AP) — Ukrainian strikes disrupted power and heating to two major Russian cities near the Ukrainian border, local Russian officials reported Sunday.

The report comes as Russia and Ukraine have traded almost daily assaults on each other’s energy infrastructure and U.S.-led diplomatic efforts to stop the nearly four-year war have not advanced.

Elsewhere, Ukraine’s top diplomat accused Moscow of deliberately endangering nuclear safety, as he said Russia’s mass drone and missile attack on Friday struck substations that power two nuclear power plants.

Andrii Sybiha’s comments came as Moscow and Kyiv continue to blame each other for strikes that severed the main power supply for weeks to Europe’s largest atomic plant.

Power knocked out in two Russian cities

A drone strike temporarily caused blackouts and cut heating to parts of Voronezh, regional Gov. Alexander Gusev said. He said several drones were electronically jammed during the night over the city, home to just over 1 million people, sparking a fire at a local utility facility that was quickly extinguished.

Russian and Ukrainian news channels on Telegram claimed the strike targeted a local thermal power plant.

A missile strike late on Saturday also caused “serious damage” to power and heating systems supplying the city of Belgorod, local Gov. Vyacheslav Gladkov reported the following morning. Some 20,000 households were affected, he said.

Belgorod had a population of some 340,000 people at the last census in 2021, and is the administrative center of a region of the same name.

Russia’s defense ministry said Sunday that its forces destroyed or intercepted 44 Ukrainian drones during the night that flew over two southwestern regions, Bryansk and Rostov. The statement made no mention of either the Voronezh or Belgorod provinces, nor specify how many drones Ukraine launched.

Months of Ukrainian long-range drone strikes on Russian refineries have aimed to deprive Moscow of the oil export revenue it needs to pursue the war. Meanwhile, Kyiv and its western allies say Russia is trying to cripple the Ukrainian power grid and deny civilians access to heat, light and running water for a fourth consecutive winter, in what Ukrainian officials call “weaponizing” the biting cold.

Strikes endanger power supply to nuclear plants

Russia’s mass drone and missile strikes Friday hit power substations that supply two of Ukraine’s nuclear power plants, according to Ukrainian Foreign Minister Andrii Sybiha.

“Russia once again targeted substations that power the Khmelnytskyi and Rivne nuclear power plants,” Sybiha said in a statement on X late Saturday. “These were not accidental but well-planned strikes. Russia is deliberately endangering nuclear safety in Europe.”

Sybiha called for an urgent meeting of the International Atomic Energy Agency board of governors to respond to the risks posed by the attacks.

“We also urge all states that value nuclear safety, particularly China and India, to demand Russia stop reckless attacks on nuclear energy that risk a catastrophic incident,” he said.

Moscow’s massive attacks on Ukraine’s electricity infrastructure last winter have heightened scrutiny over the Ukrainian Energy Ministry’s apparent failure to protect the country’s most critical energy facilities near nuclear power sites, according to several current and former officials who spoke to the AP.

Russia’s Lavrov says he’s ready to meet Rubio

Elsewhere, Russia’s top diplomat said Sunday that he was ready to meet U.S. Secretary of State, Marco Rubio, to discuss the war in Ukraine and mending bilateral ties.

“Secretary of State Marco Rubio and I understand the need for regular communication,” Foreign Minister Sergey Lavrov told Russia’s Ria state agency, weeks after efforts to organise a summit between the Russian and U.S. leaders were put on ice.

But Lavrov insisted that peace can’t be achieved without “taking Russian interests into account,” a phrase Moscow has previously used to signal it is standing firm in its maximalist demands for Ukraine. Lavrov added that the Kremlin will not drop its claim over Crimea, the Black Sea peninsula it illegally annexed from Ukraine in 2014.

Trump’s hesitancy in meeting Russian President Vladimir Putin has come come as a relief to European leaders, who have accused the Kremlin of stalling for time with diplomacy while trying to gain ground on the battlefield.

Ukraine has repeatedly voiced readiness for the ceasefire and direct peace talks proposed by the Trump administration, while Moscow has held out for more favorable terms.

The U.S. and Russian presidents last met in Alaska in August, but the encounter did not advance Trump’s stalled attempts to end a war that began with Russia’s full-scale invasion in February 2022.