CenturyLink, Inc., and the unions representing roughly 1,800 Minnesota workers failed to reach a new labor agreement before their existing contract expired Saturday night, but the two parties have agreed to a day-to-day extension of the former contract as negotiations continue.

CenturyLink, the Communications Workers of America (CWA) District 7, and the International Brotherhood of Electrical Workers, announced the extension on Sunday. Workers will remain on the job under the terms of their current contract, and the two parties will continue to negotiate a new labor agreement, spokespeople from both parties told Twin Cities Business on Monday.

News that the two sides will continue negotiations comes about a week after the CWA said that more than 88 percent of its voting members authorized a strike in the event that a “fair contract” cannot be reached with their employer.

The extension includes a clause that prohibits workers from striking or the company from locking out employees—but either party can terminate the contract extension with 24 hours of notice, CWA spokesman Al Kogler said. The union’s goal is to negotiate a fair contract, and a strike is a last-resort tool, he added.

“We remain hopeful that we can reach an agreement in the near future,” Kogler said.

CenturyLink spokesman Mark Molzen, meanwhile, said that the company was “pleased to announce the day-to-day extension,” and the company remains “optimistic that we’ll be able to reach an agreement.”

The labor contract affects 13,000 workers in Minnesota, the Dakotas, Iowa, Nebraska, and several other states extending to the west coast. The workers are former employees of Denver-based Qwest Communications, Inc., which in 2011 merged with Monroe, Louisiana-based CenturyLink.

Of the roughly 1,800 Minnesota workers covered by the contract, about 1,600 are based in the Twin Cities, according to Kogler. Negotiations began in mid-August, and the union has cited rising health care costs and the outsourcing of jobs overseas as key sticking points.

Molzen said last week that CenturyLink believes it is “critical to maintain competitive wages and benefits for employees while working to improve cost structure.”