WW3 threat raised as US grants Ukraine permission to fire its missiles INTO Russia - as Kremlin warns of 'escalating tensions'

The Kremlin has accused the West of 'entering a new round of escalations in tensions', after US president Joe Biden lifted restrictions on Ukraine using American weapons for direct attacks on Russian soil. 

Two US officials confirmed that the US has lifted the restrictions, after officials from the White House, the US military and the State Department spent weeks discussing Ukraine's usage of the weapons behind closed doors. 

Ukraine will only be allowed to use the weapons to defend the northeastern Kharkiv region, which is currently bearing witness to a drawn-out brawl for control of the region. 

Russia was furious at the news of the US' decision, launching strikes on the city of Kharkiv, the second-largest in Ukraine, that killed three people and wounded 23 others, including two children. 

The US, along with the rest of the West, has largely resisted Ukraine's pleas to be given permission to use Western missiles on Russian targets, anxious that this would draw NATO too close to the conflict. 

But ahead of a NATO meeting in Prague on Thursday, the bloc's chief Jens Stoltenberg had said repeatedly that it was time for members to reconsider limits on strikes inside Russia.

French President Emmanuel Macron had also insisted this week that Ukraine be allowed to 'neutralise' bases in Russia used to launch strikes.

German Chancellor Olaf Scholz has remained cool to the idea, though his country did promise Ukraine a new package of military aid worth 500million euros (£426million) on Thursday.

As the West further deliberates the matter, Kharkiv police warned that residents could still be trapped underneath the rubble of buildings downed by the strikes. 

'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.