OTTAWA — NDP Leader Thomas Mulcair wasn't the only person Prime Minister Stephen Harper reached out to in the last week to talk about the Quebec election and possibility of a third referendum that could split the country apart.

The Huffington Post Canada has learned that Harper telephoned provincial premiers from coast to coast and sat down with the two main opposition leaders in Ottawa.

"I think from the prime minister's point of view it was to ensure that everyone understood the seriousness of the election for the country and not to take it lightly," said a senior official in the office of a premier representing one of Canada's larger provinces.

Quebec premier and Parti Quebecois Leader Pauline Marois announced a spring election for April 7 on Wednesday. Polls suggest the sovereigntist party is headed for a majority.

Provincial sources say Harper wanted to ensure that leaders supporting the federalist cause would speak with one voice — and not get lured into any provincial or federal debates with Marois during the campaign which could give her further ammunition.

"Let's not inflame or set anything off with regards to the federalist movement," recounted one senior official in a premier's office on the east coast who requested anonymity. Once the dust settles, the message was there may be an onus on the first ministers to speak to the importance of the federation and nation building, the person added.

Harper is deeply unpopular in Quebec. He only has five MPs in the province and is very aware that if the PQ receives a majority, a third referendum could be around the corner.

Marois is being coy on the issue.

"I'm not going to discuss strategy in public but there is no promise to hold a referendum and there is no promise not to," she said Thursday.

The meetings and phone calls to the premiers were intended to be confidential.

"In the interest of having open dialogue and where they can trust us, we are not going to sit down with them for an hour and then jump out to a media event and spill the beans about what was said. And I think this is a pretty sensitive topic so I think that all the provinces [respected that]," a senior adviser to a third provincial premier said.

"I was kind of surprised to see Mulcair doing that yesterday," the person added, referencing a CBC story about Harper seeking the NDP leader's advice on Quebec, which Conservatives believe the NDP leaked.

"I thought it was kind of surprising that you would take a subject like Quebec and try to use [meetings] that are pretty standard and happen up there as well [in Ottawa] to your own benefit," the source from a Western province said.

Harper spokesperson Jason MacDonald told HuffPost the prime minister regularly speaks to premiers and leaders of the opposition.

"The substance of the conversation is, as always, private," he said.

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