Lufthansa, Germany's national carrier, wants to prevent landing slots at Berlin's new airport being awarded to Emirates Airline.
The airport is due to open next year and the German company aims to block the Dubai carrier's bid for slots because it believes the airline has an unfair advantage in its services between the two countries.
"We think there is a big imbalance in the allocation of slots," said Wolfgang Weber, a Lufthansa spokesman.
"Emirates already flies to four airports in Germany while we only fly to one destination in Dubai. They have between five and six times more business on that route as a result," he said.
"We can't predict what decision the German government will take. We can only express our opinion," Mr Weber said. "There is no bilateral air traffic relationship with any other country that is as unequal as between Germany and Dubai."
He said other European countries including France and the UK were more restrictive in their slot allocations to Emirates than Germany was.
Harald Wolf, the deputy mayor of Berlin, was reported as saying Lufthansa was pushing the federal government to refuse Emirates direct flights to the capital through the Berlin-Brandenburg International Airport, which is nearing completion.
Europe's top national carriers, including Lufthansa, British Airways and Air France-KLM, have said they are increasingly concerned about the expansion of Emirates and other major Gulf carriers, such as Etihad Airways and Qatar Airways.
Emirates declined to comment yesterday.
The companies clashed last year after the airline accused Lufthansa in June of making "false and deliberately misleading" claims designed to block the Dubai airline's request for additional access in Germany.
The carrier said a document distributed by Lufthansa to media and German policymakers in April contained 19 "errors and distortions", including incorrect portrayals of Emirates' business model, the status of its landing rights in Germany and the frequency of flights to the country.
Emirates made its response in a 10-page report entitled Tearing Down the Other Wall - believed to be a reference to protectionism.
The current spat is the latest in a long-standing war of words between the two aviation giants and underscores the determination of Lufthansa and other flag carriers such as Air Canada to make it harder for Emirates to expand into their home markets.