Western leaders fear Vladimir Putin could unleash devastating thermobaric rockets on Ukraine after fierce resistance slowed the Russian army's advance, The Telegraph can disclose.
Citizens in the capital, Kyiv, were armed with thousands of machine guns and crude bombs as they fought back against the Russian president's gathering forces. On Friday night, the city was under fierce bombardment after a day in which the army failed to make enough progress to topple the government.
Russian forces were primed to "storm" Kyiv on Friday night, said Volodymyr Zelensky, the Ukrainian president, in an address at 12.30am Ukrainian time: "The night will be harder than the day. At night they will storm, you can not give up the capital. We must survive this night."
Ukraine said on Friday night that it had shot down an Il-76 Russian transport plane 20km from Kyiv with more than 100 paratroopers on board.
Western officials on Friday briefed their serious concern that Putin would order the deployment of thermobaric weapons, which can reduce cities to rubble and would cause huge loss of life.
Thermobaric missiles contain a highly explosive fuel and chemical mix and send out supersonic blast waves that can rip buildings and bodies apart. Officials said their use would cause "indiscriminate violence".
The Russian Tos-1 Buratino weapons are understood to have crossed into Ukraine, although they have yet to be used. Moscow has previously employed them in Chechnya and Syria.
One official said the West was "very concerned at the attitude they [Russian forces] would adopt" if Ukrainian resistance continued to hold up.
A spokesman for Zelensky said on Friday night that his country is in talks with Russia to arrange a time and place for talks, adding: "Ukraine was and remains ready to talk about a ceasefire and peace."
The Russian army was bogged down in fierce fighting across the whole of Ukraine, including the first skirmishes in Kyiv itself. The first Russian armoured vehicles were seen in a northern suburb, a few miles from the Ukrainian parliament, in the early hours of Friday morning but met stiff resistance.
At least one fighter jet was shot out of the skies above Kyiv, while at least three Russian special forces soldiers trying to infiltrate the capital were detected by local intelligence and shot and killed in a gun battle caught on mobile phone footage.
Ukraine's military claimed on Friday afternoon that 2800 Russian troops had been killed or wounded, 80 armoured vehicles destroyed and 17 jets and helicopters downed across the country.
In Kyiv, the Russian army on Friday night resumed its bombing campaign after slow progress in the full-scale invasion, which Western intelligence believe had been intended to overthrow the Ukrainian government within 48 hours.
Air raid sirens sounded in the capital and its mayor, Vitali Klitschko said: "The situation now – without exaggeration – is threatening for Kyiv. The night, close to the morning, will be very difficult."
Power stations were targeted, according to Klitschko, who picked up an AK-47 to help defend his city.
On Friday night, China, a staunch ally of Moscow abstained on a UN Security Council resolution to condemn Russia's "aggression" against Ukraine.
China and Russia - important trading partners - have historically been in alignment on major issues, including most recently Moscow's military involvement in Syria.
Russia vetoed the motion.
Nato announced that it was activating its Response Force for the first time in "collective defence", meaning it is ready to fend off any incursion by Russia into Nato territory.
James Heappey, the Armed Forces minister, announced that the UK would send more tanks and troops to Estonia "earlier than planned" to reinforce the Nato ally in the wake of Russia's invasion of Ukraine.
The move will double the numbers in Estonia from 600 to 1200, with the deployment of soldiers from the Royal Tank Regiment and Royal Welsh battle groups beginning immediately. "Those doubled-up force levels remain indefinitely," said Heappey.
The Ukrainian army has remained intact and has not fractured, as the Kremlin had hoped, under the onslaught that began on Thursday morning.
As well as mobilising its reservists, Ukraine ordered all adult males under 60 to remain inside the country, and by the middle of Friday had armed its civilian population with 18,000 sub-machine guns.
The government posted online instructions for how to manufacture crude Molotov cocktail bombs in a further bid to hold up a Russian advance.
Ukraine's defence ministry announced: "We urge citizens to inform us of troop movements, to make Molotov cocktails and neutralise the enemy."
The army also blew up bridges on the road to Kyiv from the north, from where Russia had launched a two-pronged advance into the capital. Ukrainian troops blocked roads into the city in wait for the enemy.
Volodymyr Zelensky, the Ukrainian president, who had been in hiding after being identified as Russia's number one target, ventured into the streets as darkness fell in Kyiv on Friday.
He issued a rallying cry to Ukranians, saying: "We're all here. Our military is here. Citizens in society are here. We're all here defending our independence, our country, and it will stay this way."
Zelensky condemned Joe Biden, the US president, and his administration, accusing "the most powerful country in the world of looking on from a distance" while Ukraine was under siege.
He said his country had been "left alone" by the West, adding: "When bombs fall on Kyiv, it happens in Europe, not just in Ukraine. When missiles kill our people, they kill all Europeans."
In a sign of Putin's increasingly bizarre behaviour, the Russian president on Friday called on the Ukrainian army to overthrow the country's leadership, whom he called "terrorists" and "a gang of drug addicts and neo-Nazis".
Putin told a televised meeting with Russia's security council: "I once again appeal to the military personnel of the armed forces of Ukraine: do not allow neo-Nazis ... to use your children, wives and elders as human shields."
Evidence that his plea would fall on deaf ears was clear from the acts of courage displayed by Ukraine's soldiers.
On Snake Island, an entire garrison of 13 Ukrainian border guards was killed after refusing to surrender to the Russian Navy. In a message of defiance, they told Russian forces: "Russian warship, go f--- yourself".
Zelensky said the men had died heroically and each would be awarded posthumously the title of Hero of Ukraine.
Rifts between the UK and US began to open up over how to deal with Putin.
Biden has so far ignored Britain's calls to cut Russia from the Swift banking payment system. The UK Government is said to be frustrated by the US failure to block Russia's access to the Swift platform, which allows cross-border financial transactions and is used by more than 11,000 banks and financial institutions.
There were tearful scenes along Poland's border on Friday as guards separated fathers and brothers from their families because of the martial law order, which prevents men over 18 from leaving Ukraine.
At least 50,000 Ukrainians have crossed into neighbouring European countries, including 30,000 in Poland and 17,500 in Moldova, according to the United Nations refugee agency.
Pope Francis on Friday made clear his anger at the Russian invasion with an unprecedented surprise visit to the Russian embassy in the Vatican during which he expressed his "great pain and concern".
It came as Russia warned Finland and Sweden of "military consequences" if they joined Nato, amid growing support for the move in the Nordic nations.
Meanwhile, it emerged that the timing of the Russian invasion had caught the head of German intelligence off guard after he was trapped in Kyiv as forces advanced.
Despite repeated warnings from the US and its allies, Bruno Kahl, the head of Germany's BND foreign intelligence service, had to be rescued over land in a two-day journey by special forces when the country's airspace was closed.
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