The United States said Iranian military trainerswere in Crimea helping Russian forces operate Iranian-made drones to attack targets in Ukraine, adding an alarming strand to a war that has heightened geopolitical tensions.

Ukraine and Russia: What you need to know right now

Fighting

• A series of blasts rocked the Ukrainian city of Kharkiv early on Friday morning, regional governor Oleh Sinegubov and mayor Ihor Terekhov said.

• Four people were killed when Ukrainian rocket artillery struck a ferry crossing in the Russian-controlled Ukrainian city of Kherson late on Thursday, the Moscow-appointed deputy regional governor said.

Diplomacy

• The Ukrainian foreign minister said he had discussed in detail Kyiv’s request for air and missile defence systems and technology with Israel’s prime minister.

• UN chief Guterres has “spoken up very clearly” about Russia’s war in Ukraine and has not stopped communication with Moscow, a UN spokesman said after Russia signalled cooperation with UN officials could be at risk.

Power plants

• Russia is attacking Ukrainian power plants because it wants to force people to leave their homes and move westward to European Union nations, President Zelenskiy said.

• Ukrainians turned off domestic appliances, wrapped themselves in blankets to keep warm and remained defiant as they faced the first nationwide electricity outages of the war.

Economy

• Britain imposed sanctions on three Iranian military figures and a defence manufacturer for supplying Russia with drones to attack civilian and infrastructure targets in Ukraine.

• Several countries aired frustration with Germany’s refusal to cap gas prices as European Union leaders looked set to end yet another debate on the bloc’s response to the energy crunch aggravated by Russia cutting gas flows following its invasion of Ukraine.