HALIFAX -- The Nova Scotia government set the stage Monday for a showdown with some of its unions, tabling a bill that would merge the number of bargaining units in the health-care system from 50 to four by April 1.

The government is touting the bill as a way of streamlining bargaining to reduce the number of times it negotiates new collective agreements with its unions, while the unions maintain a single bargaining association would best represent the interests of workers.

Shortly after tabling the bill in the legislature the Liberal majority government moved to fast-track the legislation.

Liberal house leader Michel Samson said the bill would be pushed through second reading with an all-day sitting on Tuesday with the law amendments process slated for Wednesday.

Samson said the sudden rush was to guard against potential moves from the unions such as a wildcat strike.

"We've made it clear Bill 1 is a priority," said Samson.

Earlier, workers from four of the province's major public sector unions were quick to show their disdain for a bill they say will deprive them of the right to choose who represents them.

About 500 union members marched around the legislature, some carrying signs calling Premier Stephen McNeil a dictator and chanting for his resignation. Some had come from as far away as Cape Breton and Yarmouth.

Lisa Gentile, a daycare worker from Glace Bay, said it's clear what the Liberal government is trying to do.

"As I see it they are trying to break the unions and they are going to start with health care and work their way through," Gentile said.

Health Minister Leo Glavine said the Health Authorities Act, later designated as Bill 1, would require workers who do the same types of jobs to be represented by the same union.

A mediator would determine which unions represent the various groups of workers in the health-care system with input from the unions and the workers' employers.

"The mediator will work towards a settlement of those groups so that we have a dramatically reduced number of bargaining sessions year in and year out," said Glavine.

But Danny Cavanagh of the Canadian Union of Public Employees said the legislation is heavily weighted in favour of the employers because they would benefit from the mediation and arbitration phases.

"What if the employers come to the table and continue to say, 'No?' " said Cavanagh. "Then the mediator or the arbitrator, who'll be the same person, gets to pick stuff and that's not fair."

The unions have said they want to form a bargaining association to avoid splintering their members in contract negotiations, an idea that Cavanagh backs as the best way to ensure workers' rights are protected.

Under the proposal, the association would negotiate collective agreements for different unions, without workers changing which unions they belong to.

But Joan Jessome, president of the largest of the unions -- the Nova Scotia Government and General Employees Union -- said the intent of the legislation is to break up the current bargaining units.

She called the mediation provision "a farce."

"We represent all four groups right now and they want us to go to the table and horse trade our members?"

Glavine said wages, benefits and pensions would not be affected by any of the changes in the legislation and some workers might not change unions if an agreement can be reached in mediation.

Barring that, the process would go to arbitration where an arbitrator would decide union representation. The government wants uniformity in the representation of nurses, technologists, administrative and support workers.

The government said once the law is passed by the legislature, the mediation process would have 45 days to reach agreements. If the process ends up in arbitration, there would be an additional 45 days added to the process.

Under the law, there would be a freeze on negotiations, as well as a prohibition on strikes and lockouts, until April 1, the date that has been set to merge the province's 10 health authorities into two operations.

Leaders of the province's public sector unions have promised to fight the bill, arguing it is an attack on labour rights.

Glavine said the section of the bill that would reduce the number of health authorities will lead to estimated savings of $5 million or more a year in senior executive salaries and board expenses.

The merger was a major part of the Liberals' election platform, which promised $13 million in savings from the change, but Glavine said the government has decided to take a more cautious approach on changes to the way it administers the health-care system.

"The $13 million will eventually come," he said. "Really what we are doing with this act is setting down a foundation for probably five to seven years of change in the system."

Acting NDP leader Maureen MacDonald said her party would not support the legislation.

Progressive Conservative Leader Jamie Baillie wouldn't say what his party would do, but he said he was concerned about a bill that doesn't allow people to choose their representation.

"I have a hard time understanding why the government is against allowing health care workers to pick a union," said Baillie.

The Liberal government holds 33 in the legislature to the 10 Progressive Conservatives, seven NDP members and one independent.