Normal operations resumed Wednesday afternoon at General Motors' two Oshawa, Ont. car assembly plants, which had been left idle by a GM employee strike in the U.S. that has now been resolved.

Workers went back to work in time for the evening shift, which starts at 2:30 p.m.

But some Oshawa GM employees still felt anxious, saying they will have to fight for their jobs when they negotiate a new contract with management next September.

"I think the company is going to want more money, which will mean cuts," one worker told CTV Toronto.

Another employee said anyone who has worked at either plant for less than five years should be nervous.

"I think it's going to affect them a lot," he said.

The two plants, which rely on parts from south of the border, were shut down Tuesday after 73,000 unionized employees went on strike at GM's 80 U.S. facilities.

However, United Auto Workers President Ron Gettelfinger announced that a tentative deal was reached Wednesday and that employees would return to work across the U.S.

GM Canada had shut down Oshawa car plant No. 1, which assembles the Chevrolet Impala and Monte Carlo, at 3 a.m. Tuesday. The No. 2 line, which produces the Pontiac Grand Prix and Buick Allure, was closed at 2:30 p.m. Tuesday.

The two Oshawa plants employ 5,600 people.

The Oshawa pickup-truck plant, which employs 3,900 people, remained open during the strike.

GM spokesman Stew Low said the company's transmission factory in Windsor, Ont., which shut down during the two-day strike, would resume operations by Thursday.

The company's power-train-component plant in St. Catharines, Ont., remained in operation during the strike.

Canadian Auto Workers President Buzz Hargrove said the resolution has a broader impact on Canadian auto workers.

"There's probably about 70,000 people on layoff this morning as a result of this shutdown," Hargrove told CTV Newsnet.

"A lot of business, especially the parts industry... have been on the edge in terms of being able to survive and this strike, had it lasted for a long while, could have pushed them over the edge."

The UAW deal, if ratified, will see the union take over retiree health-care benefits, removing an estimated $50 billion in long-term obligations from GM's books.

GM is currently responsible for nearly 339,000 retirees and surviving spouses.

Aside from the new UAW-run trust to administer health care, neither side gave any further details.

However, an insider told The Associated Press that the deal also includes bonuses and lump-sum payments for workers.

The tentative contract must be reviewed by local UAW presidents on the weekend and ratified by a general membership vote by employees.

"There's no question this was one of the most complex and difficult bargaining sessions in the history of the GM/UAW relationship," Rick Wagoner, GM Chairman and CEO, said in a statement.

"The projected competitive improvements in this agreement will allow us to maintain a strong manufacturing presence in the United States along with significant future investments."

GM believes creating a union-managed trust will make the company more competitive with non-unionized automakers like Toyota and Honda, which have lower costs on employee benefits.

The nationwide strike was the first against the U.S. auto industry since 1976.

With a report from CTV's John Musselman