The United States responded by slamming what it called Russian president Vladimir Putin's "loose talk " on nuclear weapons.
President Putin admitted that his war in Ukraine could turn into a “long-term process”. Speaking to his Human Rights Council, he warned that the threat of nuclear war is growing although he claimed Russia would never be the first to use the weapons.
Putin said: "Our strategy for using them is namely as a defence, as we consider weapons of mass destruction - nuclear weapons, as built around the so-called retaliatory strike. 'When we are hit, we strike back."
In a press briefing on Wednesday, US State Department spokesman Ned Price declined to reply to Putin's remarks directly said, "We think any loose talk of nuclear weapons is absolutely irresponsible."
Price added that nuclear powers around the world since the Cold War, including China, India, the United States and Russia itself, have been clear that "a nuclear war is something that must never be fought and can never be won."
European leaders are not as alarmed by Putin's nuclear comments. In a recent interview, German chancellor Olaf Scholz says the nuclear threat from Russia has reduced.
Russia has already spoken of supposed Ukrainian attempts to detonate a "dirty bomb", drawing strong denials from Ukraine and a sharp rebuke from the United States, which had rare direct communication with Moscow to warn against nuclear use.
Neither the United States nor Russia – by far the largest nuclear weapons powers – officially has a policy of no first use of ultra-destructive arms.
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