Sotheby’s is suing Greece, its first legal action against a country, over a disputed ancient bronze horse.

Just one day before the auction of an eighth century BC statuette of a horse—estimated to fetch between $150,000 to $250,000—the Greek culture ministry sent a letter to Sotheby’s demanding the work be pulled from the sale. The document, reviewed by the Financial Times, said that the ministry found no evidence the piece “had left the country in a legal way” and included the threat of legal action.

But Sotheby’s is the one hauling the mediterranean country to court in the auction house’s first suit against a country, asking a New York judge to “clarify the rights of legitimate owners,” the Financial Times reported. Sotheby’s did pull the piece from the sale—any title dispute can dampen a work’s performance at auction—but it asserts Greece does not have a legal claim to the piece. There are records indicating the piece was held at one point by Robin Symes, a dealer accused of trading in illicitly acquired artifacts, before passing to the current owners. But the auction house cited a prior Swiss sale of the horse in 1967 and argued Greece did not put forward any evidence that the object was actually looted.