After 19 months of negotiations and a 23 day strike, Yale and union leaders have reached tentative agreements on eight-year contracts for nearly 4,000 workers, a senior Yale administrative official said Thursday.

Yale and union leaders will announce the resolution at a 7 p.m. press conference in City Hall. Yale President Richard Levin and John Wilhelm ’67, president of the parent union of locals 34 and 35, met late into the night Wednesday and briefly Thursday afternoon with New Haven Mayor John DeStefano Jr.

The resolution will end the strike by members of locals 34 and 35, the unions that represent Yale’s clerical, technical, service and maintenance workers. It was not clear Thursday afternoon when the strike, which closed dining halls and many departmental offices, would officially end.

The accords came after one of the longest rounds of contract negotiations in the two sides’ historically contentious relationship. Union members’ contracts expired in January 2002, though they were extended monthly until last March. Workers have not received raises since February 2001.

The settlement follows a flurry of bargaining this week, after a slow negotiations process in which the two sides often went months without any progress. DeStefano met with the two sides several times since the strike began Aug. 27. The mayor played a similar role during the last round of contract talks in 1996, when the two sides settled contracts in his office following two months of strikes.

Union leaders met with DeStefano Thursday morning; Levin and Wilhelm later met with the mayor for about 20 minutes. Before the second meeting, retired Local 34 member Lois Jason said she saw Levin and asked him to look at the retirees’ “Wall of Shame” in front of his office.

“He said, ‘I can’t stop now, I’m going to get a contract,'” Jason said.

Members of the locals 34 and 35 negotiating teams gathered in the Omni Hotel around 4:30 p.m. Thursday to discuss where the situation stood, Local 35 Chief Steward Meg Riccio said.

Mike Verdi, a Local 35 member who works in the Branford and Saybrook dining halls, said he was relieved the strike is ending.

“That sounds very good to me, I was wishing that would happen before Monday,” Verdi said. “I’m getting tired of hanging around here and I can’t wait to get back to work.”

Over 90 percent of Local 35 participated in the strike, while about 35 percent of Local 34 walked out. University leaders repeatedly said the low turnout was a sign that many union members did not support the strike.

This round of negotiations, which included two strikes and several high-profile rallies, began nearly two years ago, when both sides pledged to reinvent their historically acrimonious relationship. Though they met with a labor-management consultant who urged a friendlier approach to bargaining, talks disintegrated after about three months in May 2002. Since then, the two sides negotiated sporadically as rhetoric became increasingly contentious. Locals 34 and 35 held a five-day walkout in March after several months of threatened strikes.

The two sides clashed over several issues — including pensions, wages, job security and the unions’ demand that the University recognize unionization efforts by graduate students and workers at Yale-New Haven Hospital. The unions dropped the demand for the organizing drives in August, but pensions, job security in Local 34 and wages remained on the table until this week.

Thursday afternoon, Local 35 President Bob Proto said the unions would agree to an eight-year contract –they had previously asked for a shorter contract — if the University would compromise on pensions.

— Staff reporters Shinzong Lee and Will Sullivan contributed to this report.