NEW YORK (Reuters) - The National Gallery in London on Thursday won the dismissal of a lawsuit in which three grandchildren of a muse of the artist Henri Matisse sought to recover a painting they said was stolen shortly after World War Two.

FILE PHOTO: People shelter under umbrellas as the pass the National Gallery on a rainy day in London, Britain January 02, 2016. REUTERS/Neil Hall

U.S. District Judge Valerie Caproni in Manhattan said the museum and Great Britain were shielded by sovereign immunity, and the grandchildren waited too long to sue for the return of “Portrait of Greta Moll.”

Oliver Williams and Margarete Green, both of Great Britain, and Iris Filmer, of Germany, had accused the National Gallery of ignoring signs that the 1908 painting might have been stolen, and should not profit from “war-related” theft.

David Rowland, a lawyer for the plaintiffs, declined to comment, saying he had yet to review the decision.

Margarete Moll, known as Greta, sat for 10 three-hour sessions for the painting, which Matisse reworked after seeing a work in Paris by the Italian Renaissance artist Paolo Veronese.

Moll’s husband Oskar bought the painting, which was later taken to Germany.

It survived the war, but following Oskar’s death in 1947, Greta Moll left it with one of his former art students for safekeeping from looters in Switzerland.

According to the grandchildren, the student absconded with the painting, which then passed through several hands, including the Knoedler gallery in Manhattan and Lefevre gallery in London, before the National Gallery bought it in 1979.

In a 28-page decision, Caproni said the federal Foreign Sovereign Immunities Act did not require the return of the painting.

She noted that a private individual had allegedly stolen it, and said it did not matter that the painting had been displayed and merchandise depicting it had been sold in New York.

Caproni also said the grandchildren “inexcusably delayed” their lawsuit, noting that many people familiar with the painting’s history were likely dead, or if living likely suffer from faded memories.

“Plaintiffs have known for decades that the National Gallery possessed the painting,” and yet “took no steps to recover the painting until plaintiffs’ counsel began corresponding with the National Gallery in 2011,” the judge wrote.

Sarah Andre, a lawyer for the museum, said in an interview: “We are very pleased with the opinion. We are particularly pleased with the district court’s recognition that this case does not involve a taking in violation of international law.”

The case is Williams et al v. National Gallery of Art, London et al, U.S. District Court, Southern District of New York, No. 16-06978.