New London — Lawrence + Memorial Hospital’s 800 nurses and technicians will be able to return to work at 6:45 a.m. Thursday, three weeks after a four-day strike followed by a lockout kept them no closer to their patients than the picket lines on the sidewalk outside the southeast shoreline’s chief provider of medical care.

The hospital announced Tuesday evening that it would unilaterally end the lockout that it imposed Nov. 30, citing a threat of intermittent strikes that the union representing nurses and technicians denies. It was the first strike and lockout in the hospital’s 101-year history, and the first hospital strike in Connecticut in more than 25 years.

“This evening, I made the decision to have the hospital unilaterally lift the lockout of our RNs and LPN/techs effective 6:45 a.m. Thursday, Dec. 19,” L+M President and Chief Executive Officer Bruce Cummings said in a statement. “We want our staff back doing what they do best and for which they are so needed: caring for patients and serving the community.”

Cummings said L+M’s negotiating team has been unable to reach an agreement on a new contract with the union’s team, despite 16 meetings capped by back-to-back marathon sessions that began Saturday and continued into the evening Monday. There were no face-to-face meetings on Tuesday, though there was communication between the two sides, L+M spokesman Mike O’Farrell said.

The union declared the announcement a victory, citing its position that the lockout was illegal. The union had filed an injunction to end the lockout.

“Nurses and healthcare techs are declaring their unconditional return to work beginning Thursday ... a victory in their fight for quality patient care,” Matt O’Connor, spokesman for AFT Connecticut, said in a statement. “The unilateral decision by hospital administrators is a public acknowledgement of what the community has been saying throughout this ordeal: that their acute care facility cannot fulfill its mission of ‘caring for the whole region’ without its whole skilled, professional workforce.”

The tone of both statements on the end of the lockout was a departure from the dispassionate, brief statements the two sides have made about the negotiations since Saturday. After weeks of sharp rhetoric, the two sides agreed to a media blackout on the substance of the marathon sessions this weekend and Monday, citing a need not to interfere with any progress being made at a sensitive point in the talks.

The diplomatic silence, however, seemed to end Tuesday evening.

O’Farrell said the hospital decided to unilaterally end the lockout after Monday’s session ended with the union again rejecting its last offer. He declined to give specifics of that offer, other than that it was presented Sunday evening and was a revision of an earlier offer to make it more palatable to the union. The union is seeking “follow the work” language in the new contract that would ensure that any unionized nurses and technicians in non-acute-care departments moved to L+M affiliates out of the main hospital can keep their jobs. L+M had instead been offering job training, severance pay and other benefits for laid-off nurses and technicians.

“When our offer was rejected last night, it became clear that nothing was going to happen immediately, so this (ending the lockout) was the right decision to make,” O’Farrell said. “Now we take (the union) at their very public word that (intermittent strikes) will not happen.”

He said some progress was made over the last few days on some “smaller issues, but not enough to see that a solution would come soon.”

In his statement, Cummings again expressed disappointment that the union team would not take the hospital’s “last, best and final offer,” revised and presented to the union Sunday evening, to its membership for a vote.

The strike and lockout have been a financial drain on both the hospital, which paid 150 to 250 replacement workers’ salaries, travel and housing, along with expenses of increased security and full-page newspaper ads and radio spots to tell its side of the story, as well as on the workers. Going without paychecks for three weeks, many of the nurses and technicians have applied for unemployment benefits but have not yet received them.

In its statement, the union said it will continue to work for a contract that will ensure that services moved out of the hospital are still staffed by the same nurses and technicians who now do the jobs in the hospital, calling it crucial to quality patient care.

“While not realized, our members remain committed to a mutual settlement on the transfer of services that assures community access to quality care and that is provided by skilled professionals,” the statement said.

Until a new contract is signed, the nurses and technicians will be working under the terms of the contracts that expired on Nov. 16.

The announcement about the end of the lockout was made as the hospital received some negative news that was partly a result of the labor dispute.

L+M’s debt rating with Standard & Poor’s is being downgraded from an A+ to an A, O’Farrell said Tuesday.

The downgrade reflects a decline in the hospital’s operating margin for fiscal 2013 compared to the previous year, as well as expenses the hospital has been incurring related to the strike, said Lou Inzana, chief financial officer for L+M. Last week, an analyst for Fitch Ratings said his firm, which had revised the hospital’s A+ rating from stable to negative in August, was aware of the labor issues and would factor that into its next rating, due out sometime in 2014.

Inzana said Standard & Poor’s new rating is “still a very good rating for a standalone community hospital.” He added that Standard & Poor’s and other ratings agencies have been giving many hospitals nationwide a negative outlook because of increasing financial pressures from declining state and federal revenues.

The hospital was informed of the downgrade this week, O’Farrell said.

The lower debt rating means the hospital would pay a higher interest rate on any loans. However, no new major capital projects are anticipated at the present, Inzana said.

j.benson@theday.com