Since October 27th, some 130 mechanics at 10 Tesla repair shops in seven Swedish cities have been striking to protest against the carmaker’s refusal to sign a collective agreement with the metalworkers union IF Metall.

The strike has since grown into a larger conflict between Tesla and almost a dozen unions seeking to protect Sweden’s labour model, including postal workers.

As licence plates for new cars are only delivered by mail in Sweden, the blockade could stop new Teslas hitting the road there, something Tesla CEO Elon Musk branded “insane”.

In late November, Tesla filed lawsuits against the Swedish Transport Agency and mail carrier Postnord, which is owned by the Swedish and Danish states, to compel them to hand over licence plates and mail to the carmaker.

Tesla also asked the court to force Postnord to hand over some deliveries, including licence plates, while the case was pending.

“Very specific conditions are required to make such a decision and that requirement is not met,” judge Patrik Alm of the Solna district court said in a statement.

Tesla originally saw some success with its lawsuits as a separate district court issued a provisional ruling last week that the transport agency should allow Tesla to pick up licence plates directly from the manufacturer.

The ruling was however appealed, with the appellate court on Tuesday suspending the district court’s decision.

Tesla has long rejected calls to allow the company’s 127,000 employees worldwide to unionise.

However, collective agreements with unions are the basis of the Swedish labour market model, covering almost 90 percent of all employees and guaranteeing wages and working conditions.

Some 50,000 Teslas are registered in the country of 10.5 million inhabitants.

This week, the strike also started spreading to neighbouring countries and on Thursday the Finnish transport workers union AKT announced it would start blocking the loading of Tesla cars onto ships bound for Swedish ports, starting December 20.

“It is a crucial part of the Nordic labour market model that we have collective agreements and unions support each other,” Ismo Kokko, president of AKT, said in a statement.

The move comes after similar announcements by unions in Denmark and Norway earlier in the week.