Buzz Hargrove, the former head of the Canadian Auto Workers, warned Sunday that the Conservative's $4-billion aid package for the struggling Canadian auto industry may not be enough to save domestic jobs.

Hargrove's comments come a day after Prime Minister Stephen Harper and Ontario Premier Dalton McGuinty said that the federal and provincial governments would extend what they called a "short-term loan" to Chrysler and General Motors, which are teetering on the brink of bankruptcy.

But Hargrove said the deal did not include guarantees from the two companies to maintain current Canadian production levels, which account for about 20 per cent of North American production by the Detroit Three automakers.

"The responsibility of our government, if they're going to put money in now, was to guarantee the current levels of production that we have in our Canadian plants," Hargrove said Sunday on CTV's Question Period. "And none of that was part this package announced yesterday."

Ottawa will contribute $2.7 billion to the deal, while Ontario will pitch in about $1.3 billion.

The plan also includes loans for auto-parts manufacturers and other companies that are part of the auto supply industry, and promises additional credit for consumers.

Still, Thomas Mulcair, the NDP's deputy leader, told Question Period that the plan is too opaque and doesn't contain enough specifics.

"We don't know what's exactly in this deal," he said. "All this is being done on the back of an envelope at a press conference ... parliamentarians who are responsible for looking at taxpayers' money haven't had a chance to look at the details of the deal."

However, Conservative MP Rick Dykstra responded on Question Period that the automakers will have until March to submit detailed outlines for long-term survival. He added that the auto companies will have to "work very hard over the next 90 days."

Meanwhile, Liberal MP John McCallum welcomed the bridge loan announcement, but he said that Harper and the Conservatives have waited too long to deliver the package and he warned that the deal may not be enough to save Canadian jobs.

"If we put up 20 per cent of the money, we should have a guarantee that Canada has 20 per cent of the production and the jobs," he told Question Period on Sunday.

"There's some sort of production guarantee -- I don't know if it has teeth -- but my understanding is there's no guarantee whatsoever for Canadian jobs ... I don't think this government has negotiated this very well."

The former union boss Hargrove echoed those fears, and added that because Canada represents about 10 per cent of the North American car market, automakers could try to cut back Canadian operations by another 10 per cent.

That would mean the closing of another two assembly plants and at least a dozen parts plants, Hargrove said.

He argued that government officials should have received signed guarantees from the manufacturers to not only maintain current production levels, but also to secure mandates for "the next generation of vehicles."

"I've been around bargaining a long while," Hargrove said. "If you give up everything to start out, there's not much incentive or much pressure on the companies to agree to anything -- they've already got the money."

Saturday's announcement came on the heels of a proposed, $17.4-billion aid announcement on Friday by U.S. President George Bush.

Bush said that any aid, which will have to be repaid, will depend on manufacturers submitting business plans that show a vision for staying viable.

Hargrove said that any concessions by the Canadian arms of Chrysler and GM should not come on the backs of auto workers, whose union contracts have been partly blamed for the companies' economic woes.

Some reports have put workers' wages as high as $70 an hour when benefits are factored in, a figure that experts refute.

Hargrove said Canadian auto workers receive an hourly wage of between $30 and $33, but fewer of them are working at all, as production-plant shutdowns have decimated the industry in Ontario.

"To say that the auto workers have to pay more to me doesn't recognize the reality of what our members and their families and the communities that they live in are facing," Hargrove said.