Former Bloc Québécois-turned-Independent MP Maria Mourani is joining the NDP, CBC News has confirmed.
Mourani intends to run for the New Democrats in the next general election. However, she will not sit with the NDP caucus in the meantime.
The NDP has a policy on floor-crossing that states that any MP who changes parties must first run in a byelection.
The Montreal MP met with NDP Leader Tom Mulcair and other New Democrats leading up to Wednesday's announcement.
Mourani was first elected in 2006. Her riding, Ahuntsic, was held previously by the Liberals, who continued to fight hard for the seat in subsequent, close election races.
With new riding boundary adjustments coming for 2015, Mourani will be in a tough fight.
Gave up sovereignty last year
Mourani, who is of Lebanese descent, was expelled from the Bloc Québécois caucus in September 2013 over her criticism of the Parti Québécois charter of values.
Mourani told Radio-Canada that the controversial secular charter was a "political calculation" on the part of then Premier Pauline Marois. She said that independence could not be achieved without including everyone, and that it would be "impossible" without Montreal.
Last December, she told Radio-Canada that after much reflection, she came to the conclusion that the federal system is better placed to protect the rights of Quebecers.
Only two MPs remain in the Bloc Québécois caucus, now struggling under the controversial leadership of Mario Beaulieu.
One of Mourani's former colleagues, Jean-François Fortin, has formed a new political party with a former NDP MP that they say is "nationalist" but not sovereigntist.
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