The prime ministers of the Czech Republic and Austria say they oppose a plan by Germany to introduce a car toll for foreign drivers.
Unlike many European countries, Germany has no car toll.
Germany announced earlier this month it is planning to introduce toll stickers in 2016 for all cars using any roads in Germany, not just highways. Only foreign car owners would pay.
After their meeting on Thursday, Czech Prime Minister Bohuslav Sobotka said "it is not a good plan" because it discriminates against Czech drivers. His Austrian counterpart, Chancellor Werner Faymann, expressed doubts whether it is compatible with European Union law.
Faymann says all options are open for his government, including legal action against Germany, if it turns out the toll breaches EU law.