Four occupied regions in Ukraine are set to start voting in Kremlin-engineered referendums on whether to become part of Russia, setting the stage for Moscow to annex those areas in a sharp escalation of the nearly seven-month war.

Separatists and Moscow-backed officials announced earlier this week that votes would be cast from Friday through Tuesday in four provinces: Luhansk, Donetsk, Kherson and Zaporizhzhia. They claim to have widespread public support for joining Russia.

Western countries, including Canada, have described the referendums as a sham and illegal under both Ukrainian and international law.

Here’s a look at what the referendums will entail and their potential implications:

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