EDMONTON (CP) - With a groundbreaking trade pact between British Columbia and Alberta set to take effect April 1, a politically charged debate is heating up over the merits of the deal.

The aim of the Trade, Investment and Labour Mobility Agreement (TILMA) is to cut red tape in both provinces, saving millions of dollars for companies and individuals by harmonizing standards, regulations, licensing and certification.

The NDP governments in Saskatchewan and Manitoba have said they're not interested in signing on, and unions fear a watering down of standards for workers covered by the deal, including doctors, nurses, architects, engineers and teachers.

But business groups and conservative politicians say it will provide greater mobility for workers, fewer government subsidies to local firms, and a level playing field between the two provinces for contract bids and job opportunities.

Nancy Hughes Anthony, president of the Canadian Chamber of Commerce, says it's pragmatic.

"We're looking for trade all around the world and yet we can't have free trade between our own provinces," she said in an interview. "It's absolutely shocking."

A Conference Board of Canada report says the deal will create about $4.8 billion in gross domestic product and generate an additional 78,000 jobs in B.C. alone.

The Council of Canadians has denounced the pact as an intrusion on provincial political rights. They warn, for example, that it could stymie B.C. Premier Gordon Campbell's ambitious new environmental plan.

The agreement gives businesses and individuals the right to sue either province if they find that any regulation or government policy "restricts or impairs" investment.

"B.C.'s plan for higher tailpipe emissions standards on new vehicles, anti-idling measures for transport trucks, new low-carbon fuel standards and stricter rules on methane-capture at private landfills will all impair investment and are therefore vulnerable to attack under TILMA, " said the council's B.C. spokeswoman, Carleen Pickard.

Governments in the two provinces see the deal as a blueprint for other provinces wanting to remove interprovincial trade barriers.

But union leaders are skeptical.

"The deal is being oversold. Potential benefits are just not that big," said Barry O'Neill, Alberta and B.C. vice-president for the Canadian Union of Public Employees.

"Canadians should have the right to move with their work between provinces, but (these) measures will achieve this by adopting the lowest common denominator."

However, the union for Alberta's 23,000 registered nurses has spoken out in favour of the deal.

"It makes sense that you should be able to move from province to province without a tremendous amount of bureaucracy," Bev Dick of the United Nurses of Alberta said shortly after the deal was signed.

The opposition parties in Manitoba and Saskatchewan have also been pushing for their provinces to get on board.

Brad Wall, leader of the Saskatchewan Party, says his province will be left "on the outside looking in" if it simply ignores the chance for companies to supply more goods and services to Alberta and B.C.

"I've met . . . with officials in both provinces. They are waiting for Saskatchewan," Wall said in a recent speech.

Graham Parsons, a former senior bureaucrat with the Saskatchewan government, is also a strong supporter of the trade deal. He says the Agreement on Internal Trade brokered by the federal government and signed by the provinces in 1994 simply hasn't worked.

"And if something doesn't deliver, you're basically losing benefits for consumers, the public and industry," said Parsons, now president of the Organization for Western Economic Co-operation.

"The (Alberta-B.C.) deal could be expanded to include Saskatchewan and Manitoba, and the benefits would increase for all of the players."