Tesla (TSLA) faces growing union pressure in Sweden as dockworkers said Friday they would refuse to offload Tesla cars at Swedish ports, in solidarity with striking mechanics.

Though Tesla has no manufacturing facility in Sweden, the electric vehicle (EV) maker’s cars are serviced by more than 120 mechanics affiliated with the Swedish union IF Metall, which started a strike on Oct. 27. Car dealership employees and others have also joined the strike since, refusing to work with Tesla products.

Roughly 50 workers from the union at Tesla supplier Hydro Extrusions, a subsidiary of Norwegian aluminium and energy company Hydro, said they will refuse to work on Tesla’s products from next Friday as well if Tesla refuses to join a collective agreement.

In Sweden, most workers are covered by collective agreements, according to IF Metall. The terms of these collective agreements, which can cover pay, pension, working hours, perks and notice periods, are also typically negotiated on a sector-by-sector basis. However, according to the union, Tesla has not agreed to sign a collective agreement, which could raise labor costs.

Just earlier this month in Germany, unions pressured Tesla into increasing pay by 4% for about 11,000 workers. However, the German union IG Metall claims that the wages remain about 20% below those offered under collective agreements.