After allegations of sexual harassment against the opera star Plácido Domingo surfaced last summer, American arts organizations responded by canceling his appearances. European institutions, though, stuck with him. So it was notable when Spain’s National Institute of Performing Arts and Music said on Wednesday that it was canceling Mr. Domingo’s upcoming performances at the Teatro de la Zarzuela in Madrid.
The cancellation was announced a day after the union representing American opera performers, the American Guild of Musical Artists, released the results of an investigation finding that Mr. Domingo had “engaged in inappropriate activity, ranging from flirtation to sexual advances, in and outside of the workplace.” Mr. Domingo responded by saying that he accepted “full responsibility,” and that he was “truly sorry for the hurt” he had caused women.
His statement was cited by the National Institute of Performing Arts and Music, which is part of the Ministry of Culture and Sport, when it announced its decision to cancel his performances this May in the zarzuela “Luisa Fernanda” — a move the institute said it was making “in solidarity with the women affected.”
Nancy Seltzer, a spokeswoman for Mr. Domingo, said in a statement: “We are very disappointed to learn of Zarzuela’s decision to cancel the scheduled performance, but understand and respect it. Plácido Domingo hopes that he gets the opportunity to sing there again.”
It was a remarkable turn of events, especially coming in Spain, where Mr. Domingo was born and where his public support has perhaps been strongest. The May performances were meant to celebrate the 50th anniversary of his Madrid debut; Mr. Domingo has long worked to raise the profile of zarzuela, the Spanish genre of musical theater.
José Manuel Rodríguez Uribes, the Spanish culture minister, told reporters on Wednesday that “until now the situation was different; there was a presumption of innocence.”
“But from the moment that he says that what happened did happen, involving serious acts that affect many women,” he said, “we have decided that we could not maintain his presence and we informed him.”
While some other European companies said they expected to proceed with Mr. Domingo’s upcoming performances, a few said they were weighing his future.
The Teatro Real, Madrid’s major opera house, is planning a special meeting of its executive committee to discuss Mr. Domingo’s upcoming performances, Graça Prata Ramos, a spokeswoman for the company, said in an email. And the Salzburg Festival in Austria, where Mr. Domingo first returned to the stage after the allegations against him surfaced, said that it would seek further information before deciding if he would return this summer.
Another woman came forward on Tuesday to accuse Mr. Domingo of misconduct. The woman, the soprano Luz del Alba Rubio, who is from Uruguay, told The Associated Press that about 20 years ago, Mr. Domingo heard her sing and asked her to come to Washington National Opera, where he was then artistic director. Ms. Rubio was cast in several roles, she told The A.P., but after resisting Mr. Domingo’s kisses during a nighttime coaching session at his apartment, parts that he had promised her did not materialize, and she was never again hired by the company.
In the United States, the union that conducted the investigation was criticized by a lawyer representing two of the women who accused Mr. Domingo of misconduct and harassment. The union had tried to negotiate a $500,000 payment from Mr. Domingo — which it said would be used to cover the costs of its investigation and pay for anti-harassment efforts — but the deal fell apart after details of its investigation, which the union had promised to keep secret, were leaked.
Debra Katz, the lawyer, denounced the arrangement as a “secret deal” and called on the union to release the full results of its investigation. “You cannot have accountability without transparency,” she said.
The union released a statement Tuesday night calling the payment a “fine,” which it described as “to our knowledge the largest to be imposed on a union member,” and said that it was not in “exchange for A.G.M.A.’s silence or to make any ‘secret deal.’”
“Regardless of the fine imposed, A.G.M.A. was never planning to publicly release the specific details of its internal investigation, as the union had assured witnesses of confidentiality,” the statement said. “Any suggestion that the union was being paid to withhold information is patently false.”
Alex Marshall and Raphael Minder contributed reporting.