Allegheny County Chief Executive Dan Onorato yesterday said that the Port Authority union's rejection of a proposal for a new contract puts negotiations "back to square one," and he does not plan to get involved in the talks at this stage.

The proposal, from neutral fact-finder Jane Rigler, was publicly endorsed by Mr. Onorato and unanimously accepted last week by the Port Authority Board, but tossed aside by Patrick J. McMahon, president of Amalgamated Transit Union Local 85, who refused to submit it to his members for a vote.

Kevin Evanto, a spokesman for Mr. Onorato, said Mr. McMahon has not explained why he rejected the compromise or what needs to be done to resume talks.

In a letter to Mr. Onorato, Mr. McMahon yesterday suggested that if the county's chief executive has such strong feelings about the contract talks, he should get off the public airwaves and take a seat at the bargaining table.

Mr. Onorato has given several interviews in which he has encouraged the Port Authority's union to allow its full membership to vote on the proposal and possibly stave off a looming systemwide shutdown.

"When I last met with you, you indicated you had no desire to enter negotiations between the Port Authority and Local 85 until the fact-finder's report has been issued," Mr. McMahon wrote. "Obviously, by your appearance in the news media, you have now become involved, and therefore, I am urging you to not only make public statements but rather to join us in the bargaining since you are apparently calling all the shots on behalf of the Port Authority."

Members of the Port Authority Board are appointed by the county chief executive.

"If [Mr. Onorato's] presence would be helpful, when they're close to a deal, he will participate," Mr. Evanto said. "But they're back to square one. And the union and management are the ones who have to get in a room and hammer out a deal."