Amsterdam (dpa) - The Netherlands has joined Austria in filing suit against neighbour Germany for the country‘s plan to launch a motorway toll in 2019 they say would discriminate against foreigners and defy European regulations.The Dutch Transportation Ministry made the announcement on Wednesday, some two months after the Netherlands signalled its intention to join Austria‘s lawsuit, filed at the European Court of Justice, in October.It is unclear when the court will make its decision on the case."The cabinet finds, just like Austria, that the German motorway toll plan is discriminatory and violates the principles of free traffic flow," a ministry statement read. Dutch transportation officials estimate that the toll would cost Dutch drivers up to 100 million euros (117.5 million dollars) a year.Germany‘s Transportation Ministry again denied having legal misgivings over the levy, saying that the toll conforms to EU law and that the Netherlands‘ decision to join the suit changes nothing. Germany‘s opposition Green Party has called for the elimination of the toll, and Chancellor Angela Merkel‘s junior coalition parters, the Social Democrats (SPD), have expressed their own concerns."My worry is that the Transportation Ministry will spend a lot of money for the preparation for a toll that will later be impeded by the court," SPD parliamentary vice chair Soeren Bartol told dpa.Under the plan, German drivers are to be compensated for paying the toll through rebates on their motor vehicle taxes. However, drivers from other EU countries - such as Austria, Italy and France - would get no such rebate and pay the full amount.After the deduction of implementation costs, the toll is supposed to yield approximately 500 million euros each year for investments, though doubts persist about revenue figure.The law is the result of a compromise with the European Commission, which forced Berlin to make the toll fairer for non-Germans. Millions of drivers in neighbouring countries regularly use German roads.The motorway toll has long been a key demand of the Christian Social Union, the Bavaria-only sister party of Chancellor Angela Merkel‘s Christian Democrats (CDU).