A number of trucking and haulage companies from Austria, Poland and Hungary are taking their case against Germany's national minimum wage to the country's highest court, the court said on Wednesday.
The companies filed their complaint with the Bundesverfassungsgericht, or Federal Constitutional Court, on Tuesday, a court spokesman told AFP.
They object to the application of a national minimum wage to lorry drivers passing through the country even just for a few hours and the substantial paperwork associated with that.
Germany introduced a national minimum wage of 8.50 euros ($9.00) an hour on January 1, even for foreign truck drivers simply passing through to other destinations.
Germany is the only European country not to exclude transit workers from the minimum wage which it has argued was needed to stave off wage dumping.
The companies have asked the EU Commission in Brussels to examine whether the wage is compatible with European law.
Given the protests from foreign companies, Labour Minister Andreas Nahles agreed to a temporary suspension for foreign road haulage companies until the EU's rules on the issue can be clarified.
Germany's new measure had required a Polish truck driver who is heading to Spain to be paid at 8.50 euros per hour from the moment the driver crosses the German border, before reverting to the wage paid in the driver's home country on leaving German soil.
The driver's employer also faced administrative paperwork under the measure, and a fine if the driver were not paid accordingly.
Nahles has said she did not believe Germany was violating European Union rules by applying an across-the-board minimum wage, including for transiting truckers.
She said she expected a decision by Brussels between April and June.
The suspension only applies for transit journeys and not to deliveries by foreign truckers in or from Germany.