The Honolulu Advertiser and the unions that represent 600 of its employees yesterday agreed to bring in a federal mediator in hopes of reaching a contract agreement.

The employees have been working on a contract extension since the old deal expired in June 2007. Major sticking points continue to be wages and medical benefits.

The Advertiser and the Hawai'i Newspaper and Printing Trades Council have met several times in the past year, but little progress has been made.

The company had rebuffed earlier requests by the unions to bring in a mediator.

No date has been set for talks to resume.

Advertiser Publisher Lee Webber said mediation is the "reasonable next step" in the negotiation process and he said he is hopeful a third-party mediator will bring both sides to a resolution.

"The Advertiser pays among the highest wages and benefits by job category of almost any Hawai'i employer — and will continue to do so," Webber said.

"But we also have a responsibility to protect the long-term health of the newspaper in light of the uncertainties of our state and national economies — particularly the challenges faced by the newspaper industry."

Wayne Cahill, chief administrator of the Hawai'i Newspaper Guild, one of the six unions, welcomed the company's decision to agree to mediation.

"We're disappointed that it took from January to May for the company to decide that they needed to go to mediation," Cahill said.

The unionized employees in February overwhelmingly voted to authorize the unions to call a strike if the two sides fail to come up with a new contract.