Ukrainian drones have hit more Russian oil facilities and set two oil tankers ablaze in the Sea of Azov, a day after US President Donald Trump pledged to grant Kyiv a license to manufacture the Patriot air defence systems to protect its cities.
A top Ukrainian official, meanwhile, cautioned that it could take a year or more for the country to produce Patriot interceptor missiles.
The Kremlin said the licence deal reflected what it called Washington's "ambivalence" but noted it appreciated Trump's efforts to help broker a peace deal to end the war, which Russia launched over four years ago.
Ukraine's drone strikes on oil refineries and other infrastructure across Russia has triggered a widespread fuel crisis with petrol shortages and rationing in multiple regions and motorists waiting for hours to fill their tanks.
Moscow has responded by intensifying its bombardment on Kyiv and other cities, exposing Ukraine's vulnerability to ballistic missile strikes.
Ukrainian President Volodymyr Zelenskiy described the latest strikes on Russia's infrastructure as part of Kyiv's campaign of "long-range sanctions" carried out in response to Moscow's refusal to halt the fighting.
"We have long proposed that Russia end this war, and every day of delay should bring the feeling of war to where it all began - to Russia," Zelenskiy said.
A Ukrainian drone strike triggered a fire at an oil depot in the western Russian city of Tver, according to acting governor Vitaly Korolyov.
Oil reservoirs also were set ablaze by drones in Vyazniki, in the southern Stavropol region, said governor Vladimir Vladimirov, forcing the evacuation of several apartment buildings near the facility.
In the Sea of Azov, Ukrainian drones set two oil tankers on fire, according to Rostov governor Yuri Slusar, who said one of the ships was still burning and its crew evacuated.
The attack was the latest in a series of strikes on oil tankers in the area in recent days, part of Ukraine efforts to cut fuel supplies to the Crimean Peninsula, which Russia illegally annexed in 2014.
As well as strikes on oil facilities in Stavropol and Tver, Zelenskiy said Ukrainian forces hit fuel infrastructure deep inside Russia, including one in Ufa, as well as an oil-loading terminal in the Rostov region closer to Ukraine.
Russia's defence ministry said its defences downed 73 Ukrainian drones from late Wednesday into early Thursday.
Ukraine's air force said Russia fired 94 long-range strike drones and two ballistic missiles.
While 72 drones were jammed or intercepted, 19 drones and both missiles damaged 13 locations, it said.
During Wednesday's meeting with Zelenskiy on the sidelines of the NATO summit in Turkey, Trump said the US would meet a longstanding request from Ukraine and give it a license to make the Patriot air defence systems.
He also praised Zelenskiy for doing "an amazing job" - a sharp change in tone from past criticisms of the Ukrainian leader.
But setting up domestic production of the mobile, surface-to-air systems would take many months, said Serhii Beskrestnov, an adviser to Ukraine's defence minister.
Commenting on Trump's statement about the Patriot missile licences, Kremlin spokesman Dmitry Peskov offered a vague response, saying Moscow was aware of the US military support for Ukraine but appreciated Washington's declared commitment to help achieve peace.
Asked about Trump's comment that Ukrainian attacks deep inside Russia could hasten a peace settlement, Peskov reaffirmed that the more strikes Kyiv launched, the broader "security zone" Moscow would seek to carve out in Ukraine via what the Kremlin calls its "special military operation".
"It's a mistake to think that escalation and military pressure could pave the way to a peaceful settlement," Peskov said.
Peskov said President Vladimir Putin was "open to dialogue" and ready for another phone call with Trump.