Four Russian-occupied areas of Ukraine began voting in referendums on joining Russia, according to their separatist leaders, in a move that raises the stakes of Moscow’s invasion seven months after fighting began. The referendums, which are illegal under international law and dismissed as “a sham” by Western governments and Kyiv, could pave the way for Russian annexation of the areas, allowing Moscow to frame the ongoing Ukrainian counteroffensive as an attack on Russia itself. Such a move could provide Moscow with a pretext to escalate its faltering war, which has seen Kyiv regain thousands of square miles of territory this month. In an address Wednesday, Russian President Vladimir Putin raised the specter of nuclear weapons in his address, saying he would use “all the means at our disposal,” if he deemed the “territorial integrity” of Russia to be jeopardized. The votes, which are expected to take place over five days, were called by pro-Russian officials in the self-declared republics of Donetsk and Luhansk, and in Russian-held parts of Kherson and Zaporizhzhia in the south, with questions on the ballot varying slightly depending on the region. Together the four regions make up around 18% of Ukraine’s territory. The plans, which are being held under military occupation and effectively carried out at gunpoint, have been strongly condemned by both the government of Ukraine and its allies in the West. The European Union has said it won’t recognize the results and has indicated it is preparing a new package of sanctions against Russia. The outcome of “sham” secession referendums is “almost certainly already decided,” the UK ambassador to Ukraine, Melinda Simmons, said on Twitter Friday. “There will be results publicised of something that didn’t happen. I wonder whether anyone will even be called to vote,” she wrote. Putin backed the referendums in an address to the nation on Wednesday. “The parliaments of the people’s republics of Donbas and the civil-military administration of the Kherson and Zaporizhzhia regions decided to hold a referendum on the future of these territories. They have asked Russia to support this step, and we stressed that we will do everything to ensure the safe conditions for people to express their will,” he said. The separatist leaders in the four occupied regions said the referendums were underway on Friday as Ukrainian officials from occupied areas of the country accused pro-Russian forces of using coercive tactics. “The long-awaited referendum has started, which is designed to restore the fair course of things in our land, to return peace to our homes, to consolidate the status of Donbas as part of our historical Motherland – Russia,” Vladimir Bidyovka, head of the People’s Council of the self-declared Donetsk People’s Republic said in a propaganda statement published on Telegram. ‘Pseudo-referendum’ Ukrainian officials from the occupied areas on Friday accused pro-Russian forces of subverting what should be a democratic process in the referendums on secession. In both the Luhansk and Zaporizhzhia regions, local authorities have urged people to vote from home, saying that ballot boxes can be brought to them. The Luhansk region is almost entirely controlled by Russian and pro-Russian forces. But it remains contested – Ukrainian forces liberated the village of Bilohorivka earlier this week. The Ukrainian governor of Ukraine’s Luhansk region on Friday said “Russians will calculate and draw any result that is favorable to them” in what he described as a “pseudo-referendum.” “The opinion of the population has no importance,” Serhii Hayday said on Telegram, adding that an “armed man is involved in each polling station, the appearance of which should force people to meekly cast their vote.” In Mariupol, which is in the Donetsk region, “the main means of coercion for voting is door-to-door canvassing,” said Petro Andriushchenko, an adviser to Mariupol’s Ukrainian mayor, on Telegram. “The commission consists of two people with a ballot box and ballots, and two armed men,” he said. “They knock on the doors of apartments/houses, force neighbors to make people come to the commission. Coercion, coercion and more coercion. In fact, they offer to say ‘yes’ or ‘no’ directly into the barrel of a gun.” Andriushchenko is not in the city, but has been a reliable conduit for information from Mariupol. CNN is not able to independently verify his and other characterizations. “Polling stations are located in shops and cafes,” Andriushchenko said. “However, they are empty. There are no usual amenities such as polling booths there. The mark is made under the close supervision of armed people. This is what Russian democracy looks like.” Yurii Sobolevskyi, deputy head of the Kherson Regional Council, told CNN that the effort being carried out in his region has shown very little turnout. “Most people are determined not to go,” he said. “That’s why this door-to-door idea came about, because when armed people come to your house, it will be difficult and dangerous even to refuse to vote.” He said that the United Russia political party – the ruling party in Russia – has been campaigning for secession while also handing out food packages to residents. The Ukrainian mayor-in-exile of Melitopol – which is in Zaporizhzhia region, and occupied by Russia – also urged residents to boycott the vote. A ‘historical crime’ Observers say it seems unlikely that such a rushed process, in areas where many voters live close to the front lines of the conflict, can be successful or fair. Additionally, because of widespread internal displacement since the beginning of the conflict, voting databases are likely out of date. In Kherson for example, Ukrainian officials have said that about half the pre-war population have left. The Organization for Security and Cooperation in Europe, which monitors elections, condemned what it said were “illegal referenda.” A referendum organized in Crimea in 2014, which officially saw 97% of voters back annexation, was ratified by Russian lawmakers within a week. This time around, some regions plan to announce the results sooner than others. Authorities in Luhansk said they would announce results the day after voting finishes, whereas in Kherson, authorities will wait for five days after polls close. Kremlin spokesperson Dmitry Peskov indicated on Friday that if the regions announce majorities in favor of joining Russia the ratification process would be a fast one, saying that they can become part of the Russian Federation “quite soon.” When asked if that would mean any attempt of Ukraine to regain the territories would be regarded as an attack on Russian territory, Peskov said: “Of course.” Jailed Kremlin critic and Russian opposition leader Alexey Navalny called the referendums and Putin’s “partial mobilization” of citizens for his war in Ukraine a “historical crime” in a court speech on Friday. Navalny has filed an administrative lawsuit against the administration of penal colony number 6 in the Vladimir Region. “This is involving hundreds of thousands of people in the crimes that Putin commits,” the opposition leader said. “He’s like the mafia, you know? It is binding by blood hundreds of thousands of people with this mobilization and these fake referendums,” Navalny added.