The NDP has recruited a former leader of the Green Party of Quebec to run against a former New Democrat MP who defected to the Greens. Éric Ferland will run in the riding of Longueuil-Saint-Hubert to unseat Pierre Nantel, who left Jagmeet Singh's NDP to join Elizabeth May's Greens.
The tit-for-tat move comes as strong Green support in opinion polls has it competing with the New Democrats for eco-friendly votes on the left.
Nantel was first elected to the House of Commons in the NDP "Orange Wave" of 2011 and held his seat by a narrow margin in 2015.
Nantel left NDP in August after flirting with Greens
He was ousted from the NDP in August after the party learned he was talking to the Greens about switching parties. He briefly sat as an Independent.
When he joined the Greens, he said May was the only leader willing to tackle the climate change challenge.
However, Nantel caused May to face some awkward questions last week when he declared Quebec should become Independent "as fast as possible." When May said he wasn't a separatist and she wouldn't allow candidates that advocating breaking up the country to run for her party, Nantel told reporters: "Of course I'm a sovereignist."
Earlier in September, some former New Brunswick provincial NDP candidates and members issued a statement and held a news conference to announce they were joining the Greens and supporting the federal Green Party.
However, some of those named in the statement said they had not agreed to the move. The controversy touched off an exchange of accusations between the parties.
Ferland led the Quebec Greens from 1994 to 1996. He ran unsuccessfully for the federal Green Party in a 1995 byelection and was later elected as a town councillor in Frelighsburg, Que. He also founded his own green technology company, Ecosphere, with the aim of helping communities reduce their environmental footprints.
Singh will make the official announcement of Ferland's candidacy Monday at an event in the riding.
Before Nantel took Longueuil-Saint-Hubert in 2011, the area was predominantly held by the Bloc Québécois.
The last Conservative to hold the riding was Nic Leblanc, who resigned from the PC caucus after the failure of the Meech Lake Accord and joined the Bloc in 1990.
The Liberals (who haven't held the riding since the early 1980s) hope to woo voters by running Réjean Hébert, a former provincial cabinet minister for the Parti Québécois, as their candidate.