Disturbing prediction for Putin's next move: 'Horrific consequences'

• Fears Russia will deploy Thermobaric bombs

• Ukraine capital Kyiv under siege as light dawns on Saturday

• US directly sanctions Russian leader Vladimir Putin

• Ukraine president posts defiant video from the street

• Growing signs Russia wants to overthrow Ukrainian government

There are "grim" fears Russia's attack on Ukraine is set to escalate to another terrifying level as Vladimir Putin faces strong resistance from a defiant Ukrainian population.

Frustrated by the resistance, Mr Putin could resort to using a grave new weapon against civilians, Western powers fear.

According to Catherine Philp, the Diplomatic Correspondent at the Times of London, intelligence suggests Mr Putin could unleash thermobaric weapons in what would amount to unconscionable "war crimes".

"Rather grim intelligence briefings today on fears that Russians frustrated by unexpected resistance will unleash thermobaric weapons and indiscriminate shelling on Kyiv in a bid to break through with horrific consequences for civilians," Ms Philp wrote on Twitter on Saturday.

"This is grim news if you've followed Russia's military conduct in Syria and its use of these weapons in place like Aleppo. These are not weapons to be used on civilian populated centres. We are looking at war crimes."

Russia was accused of using similar weapons in Syria in 2016.

Sometimes referred to as "the father of all bombs", thermobaric weapons are said to be the most devastating non-nuclear option in Russia's arsenal and are designed to deliver a high-temperature explosion accompanied by a punishing blast wave which can rupture lungs and internal organs.

"Thermobaric bombs are known as vacuum bombs. They suck oxygen into the blast and can cause awful internal injuries, especially to the lungs," Ms Philp added.

One anonymous official reportedly expressed concerns that if Mr Putin did not meet the intended timescales and objectives he would become more indiscriminate in the use of violence.

Ukraine president makes chilling prediction

As Russian troops bore down on Ukraine's capital city Kyiv into Saturday morning (local time), the president grimly predicted that the conflict would soon intensify – the spectre of which could drag more of Europe into the fight.

There are continued reports of hundreds of casualties — including shelling that sliced through a Kyiv apartment building and pummelled bridges and schools

Heavy, frequent artillery fire and intense gunfire, apparently some distance from the city centre, could be heard on Saturday in Kyiv in the early hours of the morning, Reuters reported.

The Ukrainian military said Russian troops attacked an army base on a main Kyiv avenue but the assault was repelled.

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Meanwhile there are growing signs that Russia may be seeking to overthrow Ukraine’s government, which US officials have described as Putin’s ultimate objective. It would be his boldest effort yet to redraw the world map and revive Moscow’s Cold War-era influence.

Ukraine President Volodymyr Zelenskyy appealed for a cease-fire and warned in a bleak statement that multiple cities were under attack.

"The fate of Ukraine is being decided right now," he said in a video address on Friday night.

"Tonight, they will launch an assault. All of us must understand what awaits us. We must withstand this night."

According to a report by the Associated Press, the Ukrainian president was asked to evacuate Kyiv at the behest of the US government but turned down the offer with one official saying Mr Zelenskyy said; "The fight is here, I need ammunition, not a ride."

The Russian military has continued its advance, laying claim Friday to the southern Ukraine city of Melitopol.

Still, it is unclear in the fog of war how much of Ukraine is still under Ukrainian control and how much or little Russian forces have seized.

A large boom was heard on Friday evening (local time) near Maidan Nezalezhnosti, the square in central Kyiv that was the heart of protests which led to the 2014 ouster of a Kremlin-friendly president. The cause was not immediately known.

Five explosions struck near a major power plant on Kyiv’s eastern outskirts, said Mayor Vitaly Klitschko.

As fighting persisted, Ukraine’s military reported shooting down an II-76 Russian transport plane carrying paratroopers near Vasylkiv, a city 40 kilometres south of Kyiv, an account confirmed by a senior US intelligence official in media reports.

According to the Associated Press, the Kremlin accepted Kyiv’s offer to hold talks, but it appeared to be an effort to squeeze concessions out of the embattled Mr Zelenskyy instead of a gesture toward a genuine diplomatic solution.

US State Department spokesman Ned Price said Russia's offer was an attempt to conduct diplomacy "at the barrel of a gun" and that Putin's military must stop bombing Ukraine if it was serious about negotiations.

Ukraine said more than 1000 Russian soldiers had been killed. Russia did not release casualty figures. Mr Zelenskiy said late on Thursday that 137 soldiers and civilians been killed in the fighting, with hundreds wounded.

with wires

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