US President Joe Biden's decision to allow Kyiv to use American-supplied weapons to strike in Russia will "significantly boost" Ukraine's fightback, President Volodymyr Zelensky's press secretary has said.
Spokesman Sergiy Nykyforov said Ukraine had received "positive signals from diplomatic channels about the limited use of US-supplied weapons" in the region bordering Kharkiv.
"It will significantly boost our ability to counter Russian attempts to mass across the border," he added.
Mr Zelensky has appealed to his country's allies in northern Europe to supply his struggling military with more weapons.
Mr Zelensky - who is in Sweden - has been touring European capitals in recent days to appeal for more military aid for the Ukrainian army, which has been ceding ground to relentless Russian attacks in recent weeks.
"Today I am in Stockholm for the third Ukraine-Northern Europe summit," Mr Zelensky said in a statement on social media.
"Our top priorities are to ensure more air defence systems for Ukraine, joint defence industry projects, and weapons for our warriors, as well as global efforts to force Russia to make peace," he added.
He said he would meet leaders from Sweden, Finland, Denmark and Norway and sign several bilateral security agreements.
"Ukraine will grow stronger as a result of the support of our principled and consistent allies, as well as new security agreements," the Ukrainian leader said.
Swedish Prime Minister Ulf Kristersson meanwhile said that his country would take "important steps towards further strengthening cooperation between our countries in our support for Ukraine".
"Ukraine's cause is our cause," he added in a statement on social media.
Mr Zelensky's arrival in Stockholm comes just days after Sweden pledged military aid of 13.3 billion kronor (€1.15 billion) to Ukraine.
Meanwhile, overnight Russian strikes on a residential area in Kharkiv city killed three people and wounded at least 23 others, including two children, regional police said this morning, warning too that residents could still be trapped under the rubble.
"A man and a woman were killed as a result of an enemy munition hitting a multi-storey residential building... The fourth and fifth floors of one of the building's sections were completely destroyed," police said in a statement, adding that another munition killed a guard at a civilian production facility.
Regional Governor Oleg Synegubov noted in a Telegram post that an emergency medic was among the wounded, adding: "The enemy again used a double strike tactic, while medics, rescuers and law enforcement officers were already working on the spot."
Kharkiv Mayor Igor Terekhov said there had not been "a single military person, not a single military object" present.
Ukraine's second-largest city, Kharkiv is located just across the border from Russia's Belgorod and regularly comes under attack from Russian missiles.
Russian strikes that hit a hardware superstore in the city last weekend killed 16 people.
On the other side of the border, in Russia's southern Krasnodar region, an oil depot was damaged in an aerial attack, its governor said Friday morning, noting that a major drone incursion elsewhere in the region had been repelled by air defences.
"The situation is more serious in Temryuk district - the oil depot infrastructure there was damaged by an air strike. Three tanks with petroleum products were damaged and are on fire," Governor Veniamin Kondratyev said on Telegram, adding some workers had been wounded.
