Another day, another chapter in the weeks-long Tesla strike in Sweden – but this time a union in Denmark says it will stop offloading and transporting Tesla vehicles to Sweden as it joins in a sympathy strike with IF Metall, forming the beginnings of a Nordic port blockade against Tesla.

Today, harbor workers and drivers at Denmark’s 3F union issued a statement saying they too will take action against Tesla, meaning that Tesla can no longer circumvent the blockade by Swedish dockworkers via a detour to Denmark’s ports, reports Bloomberg. Finland’s Transport Workers’ Union will meet this week to determine their action as well. Norwegian dockworkers have said that they too will refuse to unload Tesla vehicles heading to Sweden.

Nordic countries threaten to block Tesla shipments to Sweden

If all Scandinavian transport unions join the blockade against Tesla – a very likely scenario by the look of things – that would mean its only option (other than, of course, signing the collective bargaining agreement) is to deliver vehicles by truck from Germany. Tallying up the driving distance with trusty Google Maps, from Tesla’s Giga Berlin to Malmö, to closest major city crossing the Øresund bridge from Denmark, is about a seven-hour drive one way. Of course, each truck could transport only a handful of vehicles compared to the capacity of a ship.

“Even if you are one of the richest in the world, you can’t just make your own rules,” United Federation of Trade Unions head John Trygve Tollefsen said in a statement (translated from Danish). “We have some labor market agreements in the Nordic region, and you have to comply with them if you want to run a business here. Solidarity is the cornerstone of the trade union movement and extends across national borders. Therefore, we are now taking the tools we have and using them to ensure collective agreements and fair working conditions.”

Trade unions joining in sympathy action is part of the Scandinavian labor market, and it’s not without precedent that these actions will cross borders. In 2015, pilots in Sweden joined a solidarity strike with pilots in Norway at Norwegian Air Shuttle ASA.

Last month, about 130 mechanics in Sweden who belong to the IF Metall union and service Tesla cars went on strike after the company refused their request for collective bargaining. Since, thousands of workers in Sweden have joined, from dockworkers to car dealers to even the post office workers refusing to touch anything Tesla-related until Tesla signs the collective bargaining agreement with IF Metall. Tesla’s CEO Elon Musk is notoriously anti-union and has described the actions in the country as “insane.”

Last week, Tesla filed twin lawsuits against the Swedish Transport Agency and the country’s postal service after workers refused to deliver license plates for its cars, with a court in Sweden swiftly backing Tesla. Hours after filing the court offered a temporary injunction to get the plates to the company within a week. The second lawsuit against PostNord, which is also blocking other deliveries and mail for Tesla, is still awaiting a court ruling this week.

While Tesla doesn’t like it, unions are an essential part of the Swedish labor model, with about 90% of the workforce protected by collective agreements that work to standardize pay, insurance, and pensions, as well as protect worker conditions.

The transport workers in Denmark say they will start their action against Tesla in two weeks after a mandatory two-week notice period.