Ontario government sources told The Canadian Press Wynne will announce the deal at a news conference in Toronto Monday, before flying to Quebec City to make it official with Quebec Premier Philippe Couillard.
The agreement between Ontario and Quebec will be signed one day before the other provincial and territorial premiers join Couillard and Wynne for a summit on climate change.
Ontario committed to carbon pricing in 2008 when it signed the Western Climate Initiative with California and Quebec, and they created a joint cap-and-trade system that lets polluters buy credits from companies that cap their greenhouse gas emissions.
Wynne said earlier this year that it was time for Ontario to act on that seven-year old agreement and make it "real in whatever form that takes.''
California will not be part of Monday's agreement between Ontario and Quebec. British Columbia also signed the WCI, but instead of cap-and-trade introduced a carbon tax that included a seven-cent-a-litre levy on gasoline.
Wynne and Couillard have taken the lead on the issue, and when Canada's premiers last met in January said the provinces and territories were making progress on the Canadian Energy Strategy, an initiative involving all 13 premiers focused on climate change and clean energy.
Quebec and Ontario also signed another deal to work together on climate change at a joint cabinet meeting last November, and said large projects like the Energy East pipeline should proceed only when they are environmentally sustainable. But Couillard also said he sees opportunities to grow the economy as new technologies are developed to reduce greenhouse gases.
"Nobody talks about the cost of not fighting climate change,'' Couillard said at the time. "This cost is passed to citizens too, whether it's health care, coastal erosion or spectacular weather events. This is hugely expensive for our society.''
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