Western leaders are set to convene a summit to hammer out how next to push back against the “cynical and brutal invasion” in Ukraine.

Leaders of the 30 Nato allied nations will meet on Friday, US President Joe Biden confirmed, as they come under pressure to go even further than sanctions already announced to hit the Kremlin after what Boris Johnson described as a “dark day in the history of our continent”.

Russian forces launched a full-scale invasion in the early hours of Thursday, thought to be Moscow’s most aggressive action since the Soviet invasion of Afghanistan in 1979.

By the end of the day, the Ukrainian government said 137 civilians and military personnel had been killed.

Several explosions were heard in the Ukrainian capital of Kyiv early on Friday as Russian forces pressed on with their assault.

The Ukrainian foreign minister, Dmytro Kuleba, said in a tweet just before 4am that “horrific rocket strikes” hit Kyiv in an attack he compared to the city’s 1941 shelling by Nazi Germany.

“Last time our capital experienced anything like this was in 1941 when it was attacked by Nazi Germany,” he said.

“Ukraine defeated that evil and will defeat this one. Stop Putin. Isolate Russia. Severe all ties. Kick Russia out of (everywhere).”

Earlier, the country’s President Volodymyr Zelensky ordered a full military mobilisation lasting 90 days.

Mr Johnson told his Cabinet on Thursday night that the UK could be proud of its role in supporting Ukraine, after the Prime Minister announced the “largest and most severe” package of sanctions Russia has ever faced to punish “blood-stained aggressor” Vladimir Putin.

“He said the UK could be proud of the actions it has taken so far, playing a leading role in Nato, developing a tough economic sanctions package together with our allies, and providing lethal defensive weaponry to the Ukrainian government,” a No 10 spokesperson said.

“He told Cabinet that the Ukrainian military was fighting back in defiance of Putin’s attempts to subjugate Ukraine. And he pointed to protests within Russia which demonstrated that Putin’s actions would also face resistance from within his own country.”

Foreign Secretary Liz Truss and Defence Secretary Ben Wallace spoke to their Ukrainian counterparts on Thursday night.

Ms Truss tweeted: “We continue to support Ukraine politically, economically and defensively in the face of Russia’s abhorrent invasion.”

Earlier, Mr Johnson unveiled his second barrage of sanctions to “hobble the Russian economy”.

Among the new UK sanctions introduced were measures to hit five further oligarchs, including the Russian president’s former son-in-law, and to target more than 100 businesses and individuals.

Mr Johnson said he was sanctioning “all the major manufacturers that support Putin’s war machine”, will ban Aeroflot from touching down planes in the UK and will freeze the assets of all major Russian banks, including immediately against VTB.

But he resisted calls from some MPs and Ukraine’s ambassador to London to support Nato introducing a no-fly zone over Ukraine.

Mr Johnson is understood to have pushed G7 leaders to cut Russia out of the Swift system, a type of international bank sort code.

In a White House briefing, US President Joe Biden said the move was “always an option but right now that’s not the position that the rest of Europe wishes to take”.

German Chancellor Olaf Scholz was reported to have said that certain measures should be “for a situation where it is necessary to do other things as well” when asked about Swift, while Dutch Prime Minister Mark Rutte said it was a “sensitive” issue “because it would also have an enormous impact on ourselves”.

But Ukraine’s foreign minister Dmytro Kuleba tweeted those who opposed Russia being blocked from the Swift payment system would have “the blood of innocent Ukrainian men, women and children… on their hands”.

However Mr Johnson said what he had announced amounted to “the largest and most severe package of economic sanctions that Russia has ever seen”.

It’s foul and will never be forgiven

In the US, Mr Biden also announced extra sanctions to target Russian banks, oligarchs and high-tech sectors, with more troops deployed to Germany to bolster Nato.

“Putin is the aggressor,” Mr Biden said. “Putin chose this war, and now he and his country will bear the consequences.”

He said: “Tomorrow, Nato will convene a summit – we’ll be there – to bring together the leaders of 30 allied nations and close partners to affirm our solidarity and to map out the next steps we will take to further strengthen all aspects of our Nato alliance.”

A package of further EU sanctions was announced by European Commission President Ursula von der Leyen early on Friday following a special meeting of the EU Council.

She wrote on Twitter: “First, this package includes financial sanctions, targeting 70% of the Russian banking market and key state owned companies, including in defence.

“Second, we target the energy sector, a key economic area which especially benefits the Russian state. Our export ban will hit the oil sector by making it impossible for Russia to upgrade its refineries.

“Third: we ban the sale of aircrafts and equipment to Russian airlines.

“Fourth, we are limiting Russia’s access to crucial technology, such as semiconductors or cutting-edge software.

“Finally: visas. Diplomats and related groups and business people will no longer have privileged access to the European Union.”

The UN Security Council will on Friday vote on a resolution that would condemn Russia’s military aggression against Ukraine “in the strongest terms”, and demand an immediate halt to Russia’s invasion and the withdrawal of all Russian troops.

Ukraine’s President described as heroes those who had died in the conflict.

In a video address he said Russia’s claim it was only attacking military targets as false and civilian sites also had been struck.

He said: “They’re killing people and turning peaceful cities into military targets. It’s foul and will never be forgiven.”

Mr Zelensky said all border guards on the Zmiinyi island in the Odesa region were killed on Thursday, while Ukraine also lost control of the Chernobyl nuclear site.

However local media reported troops had regained the Hostomel airport from Russian control.

The Ministry of Defence (MoD) also said it is “highly likely” Russian forces have captured the Chernobyl nuclear power plant.

A statement from the MoD said: “Russian forces have highly likely captured the Chernobyl nuclear power plant. Workers have reportedly been detained by Russian troops.”

In an intelligence update just after 1am, the MoD added it is “unlikely” Russia achieved its planned objectives for the first day of its military action in Ukraine.

“The Ukrainian Armed Forces have reportedly halted Russia’s advance towards Chernihiv,” the MoD statement said.

“Fighting probably continues on the outskirts of the city.

“It is unlikely that Russia has achieved its planned Day 1 military objectives. Ukrainian forces have presented fierce resistance across all axes of Russia’s advance.”

Mr Johnson said the UK could be proud of its role in the fightback, including for providing lethal defensive weaponry to the Ukrainian government.

He told ministers that “Putin must fail”.