In an abrupt change of course, the J. Paul Getty Museum in Los Angeles announced yesterday that it had broken off negotiations with the Italian government and made a "unilateral" decision to cede only some of the antiquities that Italy says were looted from its soil. In a six-page letter to the Italian culture minister, Francesco Rutelli, the Getty's director, Michael Brand, said the museum had decided to turn over 26 artifacts. Referring to other treasures sought by the Italians, he said that Italy had "no valid legal claim" to a prized bronze sculpture in the Getty's collection, and that evidence regarding a limestone cult statue it wanted returned was "inconclusive." Mr. Brand also wrote that the Getty would continue to study the cult statue, regarded by experts as possibly depicting Aphrodite, and would transfer title to Italy if new research lent weight to the country's claim that it had been illegally excavated on its territory. The museum's move carries significant risks for the Getty. Unlike deals to return disputed art that Italy negotiated this year with the Metropolitan Museum of Art in New York and the Museum of Fine Arts in Boston, the ceding of art by the Getty carries no guarantee of loans from Italy or other reciprocal benefits. "We will not get anything in return unless there is a change of heart on the Italian side," Mr. Brand said in a telephone interview. The Getty's decision follows nearly a year of tense negotiations over an Italian claim for 52 objects in the museum's collection. The claim rests largely on evidence that has emerged in the trial in Rome of Marion True, a former Getty curator, and Robert Hecht, an American art dealer, on charges of trading in illegally excavated antiquities. In Rome, Maurizio Fiorilli, a lawyer for the Culture Ministry, said the government had not taken an official position on the Getty's move. But noting the ministry's role as a civil plaintiff in the trial, Mr. Fiorilli said the 26 objects to be yielded would be held by the Rome tribunal as evidence supporting the indictments of Ms. True and Mr. Hecht. "If Mrs. True is found guilty, the pieces will revert to the Italian government; if she is found innocent, the Getty will decide what to do," Mr. Fiorilli said in a telephone interview yesterday. "The pieces will come to Italy not as a concession on the part of the Getty but as a seizure, the result of a procedure that is part of our legal process." Mr. Brand said the museum's parent, the J. Paul Getty Trust, reached its decision on Monday after his return from an unsuccessful meeting on Friday with Mr. Rutelli in Rome. An impasse emerged after an Oct. 5 meeting in Rome in which lawyers for the Getty and the Culture Ministry signed a memorandum meant to lead to a final joint agreement. In that document, a copy of which the Getty provided to The New York Times yesterday, the museum said it intended to return 26 objects: 25 requested by Italy and an additional artifact that its own research had determined belonged to Italy. Those objects include fresco fragments acquired in the early 1970s, red-figure Attic pottery and a rare antefix. The document also said Italy was removing six other objects from the original claim of 52. The document indicated that the Getty was preparing a formal response to the Italian claim for the bronze sculpture a life-size Greek youth believed to date from 300 to 100 B.C. and that Italy and the Getty could have joint title to the Aphrodite while further research on its origins was pursued. But relations between the sides soon fell apart, with Mr. Rutelli publicly expressing "dissatisfaction" with the talks. On Oct. 20, the Getty received a letter from a Culture Ministry lawyer "making it clear that the ministry was repudiating" the Oct. 5 document, Mr. Brand wrote in his letter to Mr. Rutelli. After news reports this month that the ministry was preparing to break off negotiations, the museum decided that Mr. Brand should go to Rome to make what he called "a final offer": the Getty would return the 26 objects promised in the Oct. 5 document and give Italy "full title immediately" to the Aphrodite, provided that the government agreed to "undertake further title research jointly." But in the meeting on Friday, which lasted more than three hours, this proposal was turned down, and no agreement was reached. In his letter to Mr. Rutelli and in the interview, Mr. Brand described the October document as an "agreement" that bound the ministry "to provide a formal agreement to the Getty within 10 days." Mr. Brand said yesterday that the ministry had reneged on that agreement by insisting on the unconditional return of the bronze and the Aphrodite and by threatening the Getty in the news media with punitive "embargoes" before it had received the museum's final assessment of Italy's claim to the disputed objects. But Mr. Fiorilli, the ministry lawyer, said in the interview yesterday that the Oct. 5 document did not have the status of an agreement and had been signed only as the "basis of a future accord" should both parties reach a consensus in negotiations. Giuseppe Proietti, the Culture Ministry official who signed agreements covering the return of antiquities by the Met and the Museum of Fine Arts in Boston, said yesterday that he was surprised to hear that the Getty had said his ministry had repudiated anything. "That's not an accord," Mr. Proietti said of the October document. Mr. Brand's characterization of the document contradicts his own comments to a reporter on Nov. 3 in which he described it as simply a memorandum between the parties. "It's not as though there's an almost final draft that we are just checking the situation on," he said then. It remains unclear whether the Italian ministry will carry out its earlier threat of breaking cultural ties with the Getty, a threat it previously used in postponing antiquities loans to the museum and in trying to win back objects from other institutions like the Met.