Voters in Alberta have rejected a proposal to begin a process that could lead to the oil-rich Canadian province leaving the country, the Canadian Broadcasting Corporation projected early on Tuesday.

With more than one million votes counted, about 76 per cent backed remaining in Canada and 23 per cent supported starting a separation process. The result is a victory for Prime Minister Mark Carney and for groups that campaigned for a united Canada.

The ballot was not a direct vote on independence. It asked whether Alberta should remain in Canada or begin a legal process that could end in a second referendum on separation. It was one of 10 questions put to voters on Monday, alongside issues such as immigration, health care and the province's constitutional powers.

More than 1.35 million Albertans, or about 43 per cent of eligible voters, cast advance or special ballots, pointing to turnout above the province's last referendum in 2021. Results were delayed after late openings forced more than 100 polling stations to extend voting hours.

Carney, who grew up in Edmonton, had urged Albertans to deliver a decisive vote for unity. "A vote against Canada is a dangerous bluff that will lead to years of deep uncertainty and lost opportunities for Albertans and Canadians," he said at a rally last week.

Premier Danielle Smith called the referendum under pressure from separatists inside her governing United Conservative Party, although she has said she opposes independence and would vote to stay in Canada. Separatist campaigners said the result would not end their movement.

Alberta holds the world's fourth-largest proven oil reserves and has long been a conservative stronghold whose politics often look more to the American West than to Ottawa. The campaign took place against a trade war with the United States and President Donald Trump's repeated suggestions that Canada could become the 51st state.