Residents of Alberta in Canada are voting in a referendum on whether the province should begin a process that could ultimately lead to independence.
The motion does not appear likely to succeed but the vote taking place at all signifies economic and political grievances gaining some sway in the vast oil-rich region.
Separatist leaders hope that a comparatively strong showing for their cause could nevertheless pressure Prime Minister Mark Carney's government in Ottawa to pay them more heed in future.
What will happen during the vote?
Polls opened at 9 a.m. local time in the provincial capital Edmonton (1500 GMT/UTC) on Monday.
They are scheduled to close at 8 p.m. that evening (Tuesday, 0200 GMT/UTC).
Results will then be published as they come in.
At least based on opinion polls, the yes/no result is in no real doubt, but as many as 1 in 3 voters might support the proposal.
What has led to the vote?
Monday's referendum is the first on the notion of breaking away from Canada in a province other than majority French-speaking Quebec, which has a better-known separatist movement founded in language and cultural differences.
The vast oil-rich state is almost double the size of Germany in terms of land mass, but is much more sparsely populated with around 5 million residents. Almost half of them live in its two main cities, Edmonton and Calgary.
Alberta's provincial government is led by Danielle Smith of the United Conservative Party while Mark Carney's Liberal Party lead the national government.
Smith herself does not advocate independence and has urged voters to oppose the motion. But she has nevertheless authorized the vote, seemingly in a bid to assuage an increasingly vocal flank within her own ranks.
Independence advocates accuse the government of stifling Alberta's oil industry, for instance through environmental regulations, and also say they contribute disproportionately to the national public purse.
"Canada has an imbalanced system which feeds the central population and government at the expense of the outlying producing provinces such as Alberta," said Cory Morgan, founder of a pro-separation organization called Pathway to Independence.
Canadian sovereignty under pressure from within and without
Carney, who grew up in Alberta, has spent much of the past week campaigning for the "stay" campaign, appealing to national pride and urging supporters to vote to provide as resounding a result as possible — even in what might not be a close race.
The renowned economist and central banker often argued that the separatist cause might be guilty of overlooking matters more significant than dollars and drilling permits.
"Canada is not a transaction between provinces. It's not about gross and net, gives and gets," he said at an event in Red Deer on Friday.
Although polls in French-speaking Quebec suggest that enthusiasm for independence — typically a minority cause — is lower than usual during Carney's premiership, the issue is never very far from the political debate. The success of the separatist Parti Quebecois in local elections this month served as a reminder of this.
Carney is also trying to maintain national unity amid pressure from Canada's nearest neighbor and biggest trade partner.
US President Donald Trump is conducting characteristically combative trade talks with Canada that have seemed in danger of breaking down in recent months.
When at his most agitated, Trump has even called for Canada to become the "51st state" of the US. He has also tried to rename bodies of water like Lake Ontario.
Why Canada's trust in the US may not recover anytime soon
Edited by: Wesley Dockery
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