Ukrainian President Volodymyr Zelensky was due to meet US special envoy Steve Witkoff on Tuesday in a bid to rescue relations that have sunk to new lows as Donald Trump has courted Moscow and Kyiv has complained about Washington withholding vital defences.
Witkoff arrived in Oslo for the talks, hosted by the leaders of Norway and Finland. Trump's son-in-law Jared Kushner was expected to attend remotely.
Zelensky met Norway's King Haakon VIII before talks with Norwegian Prime Minister Jonas Gahr Stoere and Finnish President Alexander Stubb ahead of his meeting with the US delegation.
Kyiv says Washington has lately failed to provide early warning of Russian missile launches, throttled SpaceX's Starshield satellite links that guide Ukrainian drones, and failed to deliver air defences paid for by European allies.
Washington denies deliberately hindering Ukraine's war effort. But Trump, who has waived sanctions on Russia in what he says is an effort to lower US fuel prices, has repeatedly rebuked Zelensky, and called for him to be replaced.
In the latest comments expressing warmth towards Moscow and coldness towards Kyiv, Trump said on Monday: "Russia, frankly, has been fine on Ukraine". He said Zelensky, who has rejected Russia's maximalist conditions for ending its war, was "not helping matters much", and that Kyiv should find "somebody else to negotiate".
Rubio Says US Missiles May Not Have Been Delivered Yet
US Secretary of State Marco Rubio acknowledged on Tuesday that a consignment of US air defence missiles bought by European countries for Ukraine may not have been delivered, but denied that the US had changed policy.
"The important takeaway for you is that there has not been some deliberate political directive to go out and harm Ukraine," he told journalists during a visit to India.
The Kremlin said it was hoping to set up a meeting soon between Witkoff and Russian President Vladimir Putin, an indication that Witkoff could make the latest of several visits to the Kremlin after meeting Zelensky.
As US ties with Ukraine have deteriorated, Russia has stepped up attacks on Ukrainian cities, particularly targeting power stations and fuel, despite a call from Trump for both sides to spare each other's energy systems.
Russia bombarded cities in western Ukraine overnight, targeting electricity systems and knocking out power across swathes of the country that had previously been spared.
Ukraine held back for several days last week from hitting Russian oil refineries in deference to Trump's request, but has resumed strikes after Russia showed no sign of complying. Both sides have also struck data centres.
Trump has repeatedly condemned Ukrainian attacks on Russia while saying little about Russia's far more severe attacks on Ukraine, which have grown even more deadly as Kyiv says US support has been withheld for its air defences.
Ukrainian officials said a Russian drone had struck near a petrol station on a highway heading south from Kyiv on Tuesday, killing three people and setting cars ablaze.
An attack on a warehouse near the capital also killed three. Footage released by Ukraine's emergency services showed firefighters battling a huge blaze, surrounded by twisted wreckage.
Energy facilities were attacked in seven Ukrainian regions overnight, knocking out power, and the western Lviv region was struck again during the day. Three other people were reported killed in Kramatorsk in the east.
Zelensky Speaks to Rubio
Zelensky said he had spoken with Rubio about ballistic missile interceptors, early warning of Russian attacks and "the situation with Starlink/Starshield, which needs to be restored".
"Of course, all of this comes against the backdrop of our diplomatic efforts to end this horrific war and the constant killing of people," Zelensky said in a post on X.
The deterioration of relations began 10 days ago when Trump lifted sanctions on Russian diesel in a deal agreed with Putin, which he said would help reduce prices. High fuel costs since Trump launched strikes on Iran have hurt his Republicans before midterm legislative elections on Nov 3.
Trump has since repeatedly berated Zelensky over Ukrainian attacks on Russian oil refineries, which Kyiv says are one of its few ways of fighting back after nearly five years of intensive Russian bombardment.
Over the weekend, Trump issued a broad waiver for tougher sanctions on Russia that were meant to have begun this week.
Washington denies withholding intelligence from Kyiv or imposing curbs on Starshield, the military-grade version of SpaceX's Starlink communications system.
Kyiv says the satellite receptors no longer work when mounted on fast-moving objects such as drones. SpaceX boss Elon Musk has said Starshield is controlled by the US government and any limits on its use are ultimately up to Trump.
Western European countries view defending Ukraine from Russia's invasion as an existential issue and have strongly backed Zelensky, seeking to head off a deeper rupture between Washington and Kyiv.
The United States under Trump has largely stopped providing weapons to Ukraine but lets European countries buy them on Kyiv's behalf. It also provides intelligence and technology that Europe cannot match.
A person familiar with the matter told Reuters that Defense Secretary Pete Hegseth had yet to approve the latest shipment of US weapons bought for Ukraine under the programme.