DENVER (AP) — A union representing about 350 Dex One Corp. advertising sales representatives in seven states says most have gone on strike as contract talks continue.

The International Brotherhood of Electrical Workers Local Union 1269 says workers in Colorado, Arizona, New Mexico, Idaho, Wyoming, Montana and Utah went on strike Tuesday as the union negotiates a contract to replace one that expired Friday.

The union opposes a proposal that it says would let the marketing and phone directory company outsource jobs and lay people off more easily.

Dex One spokesman Chris Hardman says the company wants the flexibility to let its partners sell Dex One services to the partners' customers.

Hardman says the average annual compensation of IBEW employees at Dex One is around $80,000 including commission and benefits.