The British music industry’s official lobbying group is set to sue the U.K. Pirate Party.

Though pro-copyright industry groups—in this case the British Phonographic Industry (BPI)—have long clashed with iterations of the Pirate Party around the world, it’s believed to be the first time such a group has sued one of those parties.

The suit centers on access to the Pirate Bay (not directly related to the party), the Swedish torrent hub that’s so well-trafficked, it’s the 76th most visited in the world. In April, the U.K. banned Internet service providers from allowing users to visit the Pirate Bay. The U.K. Pirate Party quickly found a way around that, though, by creating a proxy—or a signal rerouting—that let Brits visit the site anyway.

Loosely related “pirate parties” exist in countries around the world, and some in Europe hold high political offices. But in the U.K., as in most countries, the party mostly exists as an activist organization.

Though the BPI hasn’t filed the suit yet, it threatened in a letter to the party that it would if the proxy wasn’t taken down soon. And in a YouTube announcement, U.K. Pirate Party leader Loz Kaye declared that wasn’t an option.

“This is a legitimate service for a legitimate political end,” Kaye said.

The BPI, like its U.S. counterpart, the Recording Industry Association of America (RIAA), represents the collective interests of British record labels. Also like the RIAA, the BPI has a bad reputation among Internet rights activists: It has a history of, in the interest of shutting down sites that facilitate copyright infringement, blocking legitimate sites, too.

Buoyed at least in part by the BPI’s reputation, supporters have already offered financial support to the party, though it’s had to turn down offers of bitcoin donations because they’re unsure if that would violate donation laws. Instead, the Party has directed users to a donation page.

The BPI doesn’t have a corresponding page soliciting funds, but it did confirm that it intends to sue to ensure Brits can’t access the Pirate Bay.

Legal actions “are going to be necessary,” a BPI representative told the BBC. “It is clear that the Pirate Party are determined to continue providing access to the illegal Pirate Bay site.”

Screengrab of Kaye via YouTube