Mr Carney said: “In these separation issues, it is often advanced that, ‘vote for this and it is a free option’, ‘vote for this, and we will strengthen our hand in a future negotiation’. That is a very dangerous bluff.
“I saw first-hand what happened in the United Kingdom when the view was, ‘Vote for this, it’ll be soft and then we’ll negotiate, etc’. They’re still, 10 years later, trying to undo what people didn’t think they were voting for, but what they ended up having.”
Ms Smith has said she supports Alberta remaining in Canada.
Some have compared her stance to that of David Cameron, the then British prime minister, who called the Brexit referendum in order to silence internal Tory dissent while wanting to stay part of the EU. He resigned following the vote to leave.
Ms Smith’s party did not run on a platform of holding a referendum in the last provincial election campaign.