Russia has yet to respond to the latest ultimatum from US President Donald Trump.  

Trump says Vladimir Putin has between 10 and 12 days to make progress on ending the war with Ukraine to avoid sanctions.  

That's shrunk from the 50 days he gave the Russian leader two weeks ago.  

US correspondent Toni Waterman says there's been no official response from the Kremlin.  

She told Ryan Bridge former Russian Prime Minister Dmitry Medvedev has warned sanctioning Russia would be disastrous.  

Waterman says the leader has claimed it would start war between the US and Russia.  

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