BERLIN (Reuters) - Germany’s defense ministry said on Wednesday that its plan to give priority to the European fighter jet over U.S. competitors in a competition to replace aging Tornado jets would retain aircraft expertise in Europe and continue use of a proven system.

German Air Force Eurofighter Typhoon takes-off during the air policing scramble in Amari air base, Estonia, March 2, 2017. REUTERS/Ints Kalnins

The German Defence Ministry, in a letter to a Greens lawmaker, acknowledged that the German air force’s strategy recommended parallel use of two different fighter jet models, but said that was “not a binding guideline.”

The ministry said in December that the Eurofighter Typhoon was the leading candidate to replace its Tornado jets beginning in 2025. It said it did not share the view of German air force chief Georg Muellner, who had indicated he preferred Lockheed Martin Corp’s stealthy F-35 fighter jet.

Its latest comments came after Greens lawmaker Tobias Lindner asked the ministry to explain that position, and how it jarred with the air force’s strategy to operate two different models of fighter jets, aimed at ensuring the ability to continue operations in the event of fleet-wide grounding.

Deputy Defence Minister Ralf Brauksiepe told Lindner a final decision on the Tornado replacement would be made only after a comprehensive assessment of data provided by the aircraft manufacturers.

He said the ministry intended to buy a combat aircraft that was already available on the market, and would look primarily at the Eurofighter, as well as the Lockheed F-35 and the F-15E and F/A-18E/F fighter jets built by Boeing Co.

“A possible purchase of the Eurofighter would ensure the retention of military aircraft expertise in Germany and Europe, and value creation in our own country,” he said in the letter. “The weapons system has already been introduced to the Bundeswehr (armed forces) and is being successfully used.”

Those factors, he said, would have to be “considered” in the assessment of the different aircraft.

Lindner said the ministry’s preferential treatment of the Eurofighter underscored the problem affecting many large procurement programs. “There is a tendency to give preference to domestically developed (weapons) and value creation at home over options that are already available on the market and therefore likely less risky,” he said.

Lindner said recent German procurement programs showed that focusing too much on industrial policy factors could lead to poorly performing contracts.

The multination European A400M program, for instance, has faced huge cost overruns and technical challenges.

Brauksiepe’s letter comes shortly after the U.S. government told European Union nations that it and other non-EU countries should play a “robust” role in European defense integration, including access to future procurement contracts.

U.S. officials have provided classified briefings on the Lockheed and Boeing jets to German military officials as they prepare to launch a competition to replace the current fleet of around 90 Tornado jets - a deal that will be worth billions of euros to the winning bidder.