Washington DC – President Joe Biden said Wednesday that "pariah" Vladimir Putin is "losing" the war in Ukraine, but it is too early to tell whether the Russian president has been weakened by the mercenary Wagner group's aborted rebellion.

Asked by reporters at the White House whether Putin is now weaker, Biden said: "It's hard to tell, but he's clearly losing the war" in Ukraine and "he's losing the war at home."

Putin is now "a pariah around the world," Biden added.

In his brief remarks, Biden mistakenly referred to Russia "losing the war in Iraq" – a gaffe he also made late Tuesday when he told a group of re-election campaign donors that he'd united the West in opposing Moscow's "onslaught on Iraq."

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The White House remains cautious on interpreting the fallout from last week's extraordinary events in Russia where the forces from the Wagner group – one of the most capable parts of the Russian military in Ukraine – mutinied and threatened to attack Moscow, before reversing course.

Biden is leading a Western drive to support Ukraine's resistance to the Russian invasion, launched in February last year.