Russian President Vladimir Putin cannot remain in power, and his war against Ukraine has been a strategic failure for Moscow, US President Joe Biden said on Saturday.”For God’s sake, this man cannot remain in power,” Biden told a crowd in Warsaw at the end of a two-day trip to Poland.The unusually strong rhetoric was quickly played down by the White House, which said the president was not calling for regime change in Russia.”The President’s point was that Putin cannot be allowed to exercise power over his neighbors or the region,” the official said. “He was not discussing Putin’s power in Russia, or regime change.” During his oftentimes fiery speech, Biden warned Russia against stepping foot on NATO soil but said American forces were stationed in Europe to defend NATO allies, not to engage with Russian forces.The US president also accompanied Polish Prime Minister Mateusz Morawiecki and Warsaw Mayor Rafal Trzaskowski to Warsaw’s National Stadium, where Ukrainian refugees are being registered and provided with aid.Poland has taken in more than 2.2 million out of an estimated 3.5 million refugees who have fled Ukraine since the Russian invasion began more than a month ago. Asked what he thought of Putin after meeting the refugees, Biden said: “He’s a butcher.”