The Russian foreign ministry has reportedly warned the US ambassador that the Kremlin is on the verge of severing ties between the nations.

       Reuters reported the warning to US Ambassador John Sullivan on Monday morning as Russia continues its assault on Ukraine amid harsh sanctions by the US.

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       The foreign ministry said it told Mr Sullivan that “unacceptable statements” by US President Joe Biden about Russian President Vladimir Putin had pushed relations between the two countries to a “breaking point”.

       Last week, following Ukrainian President Volodymyr Zelensky’s joint address to Congress, Mr Biden branded Mr Putin a “war criminal” and “murderous dictator”.

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       He made the scathing remarks at the annual Friends of Ireland Luncheon on Capitol Hill on 17 March, calling Mr Putin “a pure thug who is waging an immoral war against the people of Ukraine”.

       “I think we’re in a genuine struggle between autocracies and democracies and whether or not democracies can be sustained,” Mr Biden said.

       The comments set off a war of words with Moscow, with the deputy secretary of Russia’s Security Council, Dmitry Medvedev, accusing the US and its allies of a “disgusting” anti-Russian conspiracy.

       “It will not work,” Mr Medvedev said last Thursday. “Russia has the might to put all of our brash enemies in their place.”

       Dmitry Peskov, a spokesperson for Mr Putin, told reporters: “We believe such rhetoric to be unacceptable and unforgivable on the part of the head of a state, whose bombs have killed hundreds of thousands of people around the world.”

       Mr Biden is slated to make a stop in Poland this week during his upcoming trip to Europe for urgent talks with Nato and European allies as Russian forces concentrate their fire upon cities and trapped civilians in the Kremlin’s nearly month-old invasion of Ukraine.

       Poland, which neighbors Ukraine, has taken in more than 2 million refugees from the fighting. It’s been one of the most vocal in asking fellow Nato members to consider getting more involved to rein in the bloodshed.

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       White House officials said previously that Biden had no plans to travel to Ukraine. Biden and Nato have said repeatedly that while the United States and the military alliance will provide weapons and other defense support to non-Nato member Ukraine, they are determined to avoid any escalation on their side that risks a broader war with Russia.

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