Quebec Public Security Minister Martin Coiteux says the province has asked for and will receive assistance from the Canadian Armed Forces to deal with widespread flooding that is only going to worsen.

"We are facing a situation where we are not only dealing with serious flooding, but the situation will continue to deteriorate for the next few days," he said, adding that the military will be deployed in affected areas starting tomorrow.

So far, 124 municipalities across the province are dealing with flooding, especially in the regions of Montreal, Laval, the Montérégie, Mauricie, Lanaudière and the Laurentians.

Low-lying Île Mercier and Île Verte, small islands that are part of the cities of Montreal and Laval respectively, are now deep in water and many residents have had to leave their homes.

And with Environment Canada issuing a rainfall warning, the situation is only expected to get worse.

"I'm not happy to say that but I have tell Quebecers the truth, it's going to get worse," said Coiteux. "This situation will last for a number of weeks."

Workers help build a sandbag wall in Pierrefonds. (CBC)

Federal Public Safety Minister Ralph Goodale says federal officials will work with Quebec authorities on planning the details of the military's role.

Soldiers could be deployed to distribute or position sandbags. They could also use specialized equipment in some areas.

"Citizens can rest assured that help will be provided as soon as possible," Goodale said in a statement issued late Friday. "I strongly encourage impacted residents to follow the directions and advice of their municipal law enforcement and first responders."

The exact places where military personnel will be deployed isn't known yet, but Coiteux said they would start with the hardest-hit regions and help other areas as needed.

Premier Philippe Couillard also offered his support, saying that military will be there to help Quebecers during "the difficult times that we will face together."

Worst flooding in years

Environment Minister David Heurtel described the situation as exceptional and said that Quebec had little choice but to ask for additional help.

"We haven't seen this in 55 years," said Heurtel.

Following a month of severe flooding, Coiteux promised earlier that the Quebec government will provide all necessary resources and assistance to affected regions and displaced residents.

Hydro-Québec workers push a boat with equipment on Saint-Louis Street in Gatineau. (Justin Tang/Canadian Press)

"We know it's not easy but the government is with you," said Coiteux.

The Quebec government is also offering financial compensation for residents affected by the flood. Information sessions will be held in the coming days.

Evacuations are for residents' safety, Coiteux says

Coiteux is also asking residents to evacuate if asked to do so by their municipalities or emergency services.

"If your municipal authorities say it's safest to leave your home, you must understand we are making that request solely for your safety and the safety of your family," said Coiteux. "I understand it's difficult to take that decision."

He added that measures will be taken to look after people's homes.

"If we're asking them to leave their homes, don't worry, we will be there to protect your property and your goods. We're going to be there with police forces," he said.

Some residents have left their homes on Île Mercier, but a number of others refuse to leave. (Charles Contant/CBC)

As of Friday afternoon, high water levels had forced 785 people from their homes across the province.

Prime Minister Justin Trudeau has pledged full support including funding and military assistance to Quebec and other provinces facing heavy rainfall this weekend.