Ukraine's president has warned that Russia's "sham referendums" and attempts to annex Ukrainian territory rule out any talks with Moscow as long as Vladimir Putin remains president.
Addressing the UN Security Council by video link over Russian objections, Volodymyr Zelensky urged additional military and financial support to defend Ukraine "so the aggressor would lose", and "clear and legally binding guarantees of collective security" for his country in response to Russia's latest grab for Ukrainian territory.
The referendums, slammed by Kyiv and Western allies as rigged, took place in the Russian-controlled Luhansk and Kherson regions and in occupied areas of the Donetsk and Zaporizhzhia regions – and are widely seen as a pretext for announcements that Russia is annexing the territories, just as it annexed Crimea in 2014.
Pro-Moscow officials said later on Tuesday that residents in all four occupied areas of Ukraine voted to join Russia.
Within days, it could possibly set the stage for a new and potentially more dangerous phase in the seven-month war following Russia's 24 February invasion.
Ukraine called the emergency meeting of the Security Council to respond to the referendums and the expected annexation announcements from Russia.
"Any annexation in the modern world is a crime, a crime against all states that consider the inviolability of border to be vital for themselves," Mr Zelensky said.
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He accused Russia of destroying "the main body of international law", and responding to "any proposals for talks with a new brutality on the battlefield, with even greater crisis and threats to Ukraine and the world".
"Russia's recognition of these sham referenda as normal, the implementation of the so-called Crimean scenario and another attempt to annex Ukrainian territory, will mean that there is nothing to talk about with this president of Russia," Mr Zelensky said.
"Annexation is the kind of move that puts him alone against the whole of humanity."
Many Security Council members denounced the referendums and stressed that any annexation of territory would never be recognised.
UN political chief Rosemary DiCarlo said voting on the referendums took place in polling centres and "de facto authorities accompanied by soldiers also went door-to-door with ballot boxes".
"They cannot be called a genuine expression of the popular will," she told the council.
"Unilateral actions aimed to provide a veneer of legitimacy to the attempted acquisition by force by one state of another state's territory, while claiming to represent the will of the people, cannot be regarded as legal under international law."
Britain's deputy ambassador, James Kariuki, called the referendums "illegal and illegitimate" and a violation of Ukraine's sovereignty and territorial integrity and the principles of the UN Charter.