MOSCOW/KIEV - A meeting between Russian President Vladimir Putin and Ukrainian President Volodymyr Zelensky is not being planned, Russian Foreign Minister Sergei Lavrov said Friday as heavy fighting between Russia and Ukraine dragged on.

"Putin is ready to meet with Zelensky when the agenda would be ready for a summit, and this agenda is not ready at all," Lavrov told the US news outlet NBC.

His comments came a week after US President Donald Trump met with Putin in the US state of Alaska for talks aimed at ending the three-year conflict in Ukraine. The US president also met with Zelensky and European leaders on Monday.

The latest discussions of a potential Putin-Zelensky meeting surfaced after Trump said he called Putin and started working on a bilateral meeting between Putin and Zelensky -- and possibly a trilateral one including himself -- following his talks on Monday.

Commenting on the potential meetings, Trump told reporters Friday: "We're going to see if Putin and Zelensky will be working together. You know, that's like oil and vinegar a little bit."

"They don't get along too well ... but we'll see, and then we'll see whether or not I would have to be there. I'd rather not. I'd rather have them have a meeting and see how they can do," he said.

Lavrov told NBC that Russia has agreed to show flexibility on several issues raised by Trump during his meeting with Putin.

The foreign minister previously said that Russia does not reject any formats, either bilateral or trilateral, on resolving the conflict in Ukraine, but noted that any contacts over Ukraine involving top officials need to be prepared "extremely carefully."

Zelensky on Friday said Russia is "doing everything" to prevent his meeting with Putin from taking place.

"The meeting is one of the components of how to end the war. And since they don't want to end it, they will look for space to (avoid it)," he added.

On the frontline, both Russia and Ukraine have intensified attacks on each other's energy infrastructures over the past week.

The Russian Defense Ministry said Friday that over the past week, Russian troops captured nine settlements and launched six group strikes targeting the Ukrainian military-industrial complex and energy facilities, an oil refinery, and storage sites of Ukrainian missiles, fuel, rocket-artillery weapons, and long-range drones.

During the period, Russian air defense systems shot down 25 guided aerial bombs, 11 rocket projectiles from the US-made HIMARS multiple launch rocket system, as well as 1,500 drones, it said.

Zelensky said Thursday that Russia launched one of the largest strikes against Ukraine overnight involving over 570 drones and 40 missiles. A US factory in western Ukraine was targeted, he added.

The commander of Ukraine's Unmanned Systems Forces, Robert Brovdi, announced on Friday an attack on the Unecha pumping station in Russia's Bryansk region.

The station is a crucial part of the Druzhba oil pipeline, which supplies oil to Hungary and Slovakia. Hungarian Prime Minister Viktor Orban said Friday the pipeline was subjected to repeated Ukrainian attacks over the past weeks.