Union members who work at a food distribution center in Maine are launching a 24-hour strike as part of their drive for a new contract.

United Food and Commercial Workers Local 1445 says 250 workers at the Hannaford Distribution Center in South Portland began the strike on Wednesday morning. The union's contract expired on Saturday.

"The supermarkets won't be getting the food that they need to sell on the shelves if we stay out on strike," said union president Jeff Bollen. "We don't want to stay on strike but if we don't get a good contract, we're going to be back out."

A spokeswoman for the Hannaford center's operator, Delhaize America Distribution, says the company is "disappointed" by the strike and will "fully serve its customers" during it. The company plans to meet with the union for mediated talks on Feb. 26.

The union is looking for concessions including a more attractive health insurance package and better starting wages for new union members. The union announced earlier this week that members had voted to authorize the strike.