The government of Peru yesterday broke off negotiations with Yale University over a collection of thousands of artifacts the country says were temporarily loaned to a Yale explorer nearly 100 years ago, university officials said.

The university says the some 5,000 artifacts, which include jewelry, mummies, human bones, and ceramics, were legally acquired by archaeologist Hiram Bingham on trips to Machu Picchu – the “Lost City of the Incas” – in 1911 and 1912. Bingham was the first foreigner to reach the site.

The two sides had been in negotiations over the objects, specifically those acquired during the 1912 trip, since late last year. Artifacts that Bingham acquired on a later trip in 1914 were returned to Peru in the 1920s.

Despite their belief that it was entitled to all the artifacts, the university offered the country a deal where some of the artifacts would be given in time for a museum opening in Peru dedicated to an anniversary of the discovery of Machu Picchu – Peru’s greatest cultural attraction and source of tourism.The rest of the artifacts would remain at Yale under the proposed deal.

“The collections under discussion were legally excavated and exported to the Peabody Museum at the beginning of the 20th century in line with the practices of the time, and Bingham made a good faith effort to comply with the requirements of the Peruvian government,” the university said in a statement. “We are disappointed that the government has rejected this proposal and is apparently determined to sue Yale University.”

Representatives of the Peruvian government could not be contacted for comment last night.

An impending Peruvian lawsuit joins several other similar cases against museums in America and Europe, where nations are claiming that certain artifacts or artworks rightfully belongs to them.The Metropolitan Museum of Art recently agreed to return 21 pieces of artwork to Italy after it was determined they were acquired illegally by a previous dealer. The agreement was made without any legal action and the museum wasn’t accused of any wrongdoing.

The executive director of the International Foundation for Art Research (IFAR),Sharon Flescher,said what distinguishes this case from the other repatriation claims is the fact that it rests on a special agreement made by Bingham in 1912 with the Peruvian government, and not on modern laws preventing cultural items from leaving the country.

“The laws in 1912 were very different than 2006,” she said.