MONTREAL -- Incumbent Montreal Mayor Valerie Plante received support from the city’s firefighters Monday, with the Association des pompiers saying they’ll back her re-election bid.

"This is exceptional, this is the first time this has happened," a source with the union told CTV News Montreal on Monday afternoon.

Projet Montreal will hold a news conference at a fire hall in Chinatown Tuesday afternoon as firefighters lend support to Plante and her party.

The decision is related to a longstanding beef: Back in 2014, the Coderre administration passed Bill 15, which imposed a 50/50 split of municipal pension plans..

Bill 15 was pushed by mayors and passed by the Quebec Liberal government. It shared 50-50 split pension plan deficits and non-indexation of pensions, particularly because it unilaterally changed previously negotiated agreements between employers and unions.

It left a bad taste in the mouths of several unions, including the firefighters. Coderre renegotiated with the union in 2017 as it was facing a legal battle.

- With files from CTV News Montreal's Andrew Brennan