A cease-fire was planned in the strategic Ukrainian port city of Mariupol and in Volnovakha on Saturday morning to allow for humanitarian evacuations. But the life-saving effort stalled amid reports that Russian shelling continued. "The Russian side is not holding to the cease-fire and has continued firing on Mariupol itself and on its surrounding area," said Kyrylo Tymoshenko, the deputy head of Ukrainian President Volodymyr Zelensky's office. Meanwhile, Russian media outlet RIA Novosti carried a claim from Russia's defense ministry that the firing was against Russian positions. Later on Saturday, Russian President Vladimir Putin warned that Ukrainian statehood is in jeopardy. And he likened the West imposing sanctions against Russia to "declaring war." "But thank God, we haven't got there yet," Putin said during a meeting with flight attendants. He also said if any third-party issued a no-fly zone over Ukraine, a measure Zelensky has asked for, Moscow would consider it "participation in the armed conflict." NATO had decided against a no-fly zone on Friday, lest it risk a direct altercation with Russia. In a Zoom call with U.S. lawmakers Saturday, Zelensky made an impassioned plea for help, calling for military planes and support, and an embargo on Russian oil. More than 1 million people have fled the country amid the fighting, and thousands have reportedly died.