Sending foreign weapons to Ukraine will lead to a "global collapse", Russia's foreign ministry has warned.
Sergey Lavrov, Russia's Foreign Minister, said western powers sending mercenaries and military equipment to the front lines would be a "catastrophic development".
Yesterday, Deputy PM Dominic Raab called on world leaders to support Ukraine with "everything from military hardware through to cyber resilience" to prevent a "creeping normalisation" of what Russia is doing in Ukraine.
He urged his international counterparts to supply the under-siege nation to prevent "more aggression in the future".
Meanwhile, Vladimir Putin has demanded Ukraine recognise Russia's claim to Crimea and acknowledges Donetsk and Lugansk as independent states if the war is to end.
Ukraine must also lay down their arms and distance themselves from Nato.
The demands come after reports Kremlin troops are preparing for a fresh attempt to seize Kyiv.
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As the invasion enters its 12th day, UK defence officials believe Russian troops have made minimal gains over the last 48 hours - and Putin's troops were pushed out of Chuhuiv.
But there are fears the 'humanitarian corridors' - set up to help refugees flee the fighting - are simply a way for Russia to manipulate the situation with the corridors forcing them to exit through Belarus or Russia.
Vladimir Putin 's troops have been attempting to advance towards the capital city for days but ground to a halt as the Ukrainian resistance hit supply lines.
Ukrainian President Vlodomyr Zelensky has vowed revenge after photos of a fleeing family lying dead in the street as Russian forces shelled Irpin shocked the world.
In a fiery address on Sunday, Volodymyr Zelensky promised a day of judgement after the deaths of evacuating Ukrainians.
The Ukrainian leader spoke following the tragedy in Irpin, where four members of one family were killed when missiles struck.
Meanwhile, Boris Johnson accused Western powers of "turning the other cheek" to Russia for too long.
The Prime Minister claimed the West had “failed to learn the lessons” of previous Russian aggressions that had led to the invasion of Ukraine.
In a 1,300-word essay in the New York Times, he told his counterparts “the world is watching” and urged them to match rhetoric with action.
He wrote: “Have we done enough for Ukraine? The honest answer is no.”
He set out a six-point plan aiming to tackle Vladimir Putin ’s advance.
And with more than 1.5 million Ukrainians having fled to nearby countries as Russian aggression intensifies: “We need to prepare now for even darker days ahead.”
But Mr Johnson, who was foreign secretary from 2016 to 2018, failed to acknowledge any personal responsibility for not doing more to tackle Putin.
His own party has come under fire for letting Russian oligarchs treat London as a “laundromat” to clean dirty money.
Mr Johnson himself was branded a “Putin apologist” during the Brexit campaign, when he sought to blame the EU over Russia’s 2014 annexation of Crimea..
