Bacardi has taken new legal action in its long-running rum war with Cuba, this time against banking regulators in a hunt for information about how an entity owned by the island nation last year received a U.S. license to renew the disputed “Havana Club” trademark.

Bacardi & Company Ltd. and Florida-based Bacardi U.S.A. Inc. on Wednesday filed a Freedom of Information Act lawsuit against the U.S. Treasury Department. The complaint in Washington federal district court said the U.S. government has failed to turn over documents Bacardi requested in January 2016 about the Treasury Department’s decision to reverse course and allow the state-owned Cubaexport to renew its “Havana Club” trademark.

The retroactive renewal of Cubaexport’s trademark registration, through a license issued by the Office of Foreign Asset Control, “violated well-settled United States law (and more than fifty years of U.S. foreign policy),” Bacardi’s lawyers at Kelley Drye & Warren said in their complaint.

A spokesperson for the foreign assets office, a division of the Treasury Department, was not immediately reached for comment Thursday. 

Bacardi claims to be the rightful owner of the trademark for Havana Club, a brand that was first produced in Cuba by a rival company, José Arechabala, S.A.

According to Bacardi’s lawsuit, the Arechabala family’s company “exported its rum to the United States until 1960, when armed Cuban revolutionary soldiers under the direction of Fidel Castro forcibly seized all of [the company’s] assets.” In the 1970s and 1980s, Cuba export sold an “inauthentic version of ‘Havana Club’ rum, primarily in Communist countries,” according to the lawsuit.

Bacardi argues that it obtained the rights to the “Havana Club” trademark, along with the original recipe, in a deal with the Arechabala family in the mid-1990s. The Treasury Department, according to the lawsuit, allowed a joint venture between Cubaexport and the French liquor giant Pernod Ricard to register the Havana Club trademark last year. A decade earlier, the lawsuit said, the Treasury Department had prevented Pernod and Cubaexport from renewing the trademark.

Bacardi’s request for documents about the decision, according to the lawsuit, “sought to get to the bottom of this ill-advised change in United States policy.” According to the lawsuit, it took more than a year for the Treasury Department to make an “initial” production of 32 pages in March 2017, which only came after Bacardi filed an administrative appeal.

“Notably, [the Treasury Department] produced no documents reflecting communications with other agencies, such as the Patent and Trademark Office, the State Department, or the White House—documents which surely exist and which fall within the scope of the request,” Bacardi’s lawyers argued.

The dispute arises at a time of renewed uncertainty over U.S.-Cuba relations.

In June, President Donald Trump ordered new travel and commercial restrictions while leaving in place several other measures of the Obama administration’s deal to begin normalizing relations with Cuba.

The U.S. airline industry, for instance, is pushing to deepen its investment in the Cuba market nonetheless. Last week, Transportation Secretary Elaine Chao agreed to begin a proceeding to reallocate approvals for daily flights to Havana that Spirit and Frontier forfeited earlier this year.