TORONTO - The vast majority of workers at Loblaw-owned stores in Ontario have ratified a five-year labour contract with Canada's largest grocery company, but a small cluster of stores in the province face a strike by one of the union's locals starting Friday.

The United Food and Commercial Workers union represents a total of about 30,000 Loblaw employees in the province but the strike would only affect 1,700 members of UFCW Local 175/633 at nine Zehr's and Real Canadian stores in Essex, Kent and Lambton counties.

A spokesman for UFCW Local 175/633, which voted down the tentative agreement, said the union hopes to sit down with the employer "and have some meaningful dialogue about some geographical differences that we may have in the southwest region."

Loblaw Co. Ltd. (TSX:L) reached tentative settlements with a total of three locals of the union, including 175/633, after months of negotiations and help from a provincial mediator.

Members of Local 1000A, which represents 15,000 workers at Loblaws, Real Canadian Superstores and Great Food stores, voted 56 per cent in favour of their deal while the 10,000-member Local 1977 gave 74 per cent approval for contracts at some Zehrs, Real Canadian Superstores and Great Food stores.

Scott Penner, president of Local 1977, and Kevin Corporon, president of Local 1000A, issued similar statements saying the contract was good for UFCW members.

"Among other gains, it protects the economic security of those workers who have made this company the undisputed marketplace leader in Canada," they said.

However, UFCW spokesman Ray Bromley said Local 175 has notified Loblaw that a strike will begin at 12:01 a.m. Friday, the deadline set last month by the union after months of negotiations failed to reach an agreement between the two sides.

"It will be very peaceful but people will be receiving information about why we're out on the picket line," Bromley said.

Bromley, executive assistant to Local 175 president Shawn Haggerty, said in a phone interview the union leadership has "an understanding" of the reasons for the rejection but "we need to confirm that and we certainly need to address that at some point to address that with the employer."

The area, which includes the cities of Windsor in Essex, Chatham in Kent and Sarnia in Lambton, has been hard-hit by the recent troubles of the automotive manufacturing industry.

The area is also close to two major border crossings, allowing local residents to cross easily into the United States to shop in the Detroit area near Windsor and Port Huron, Mich., near Sarnia.

Canada's largest grocery distributor and the UFCW began contract talks in April.

A tentative deal supported by UFCW's negotiators was reached last weekend after intense bargaining, including the union's threat of going on strike if a deal wasn't reached by Friday.