COLOGNE, Germany — German Air Force chief Lt. Gen. Karl Muellner has appeared to make a new push for the F-35 fighter jet to replace the country’s aging Tornado aircraft in the mid-2020s.

Speaking at an industry conference in Berlin on Wednesday and in an interview with Reuters that day, Muellner said his service needs a stealthy fifth-generation fighter capable of attacking targets from far away — a description closely resembling the advertised features of Lockheed Martin’s F-35.

The Air Force is known to favor the F-35 over three other contenders — the F-15E, the F-18 and an upgraded Eurofigher — and Muellner previously has been even more explicit about his desire to get the jets, according to experts in Germany.

Advocates believe the F-35 could quickly meet Germany’s requirements — including the need to carry U.S. nuclear bombs under NATO’s extended deterrence umbrella in Europe — and cement defense ties with the United States at the same time.

But officials at the Federal Ministry of Defence stressed that Muellner was speaking strictly from an operational point of view, leaving out financial, industrial and political considerations that would factor into a new acquisition.

“We are currently in the market survey phase,” a ministry spokesman told Defense News on Thursday, adding that the Air Force will not be the lone decider on which plane to pick. At the same time, Muellner’s opinion would be heard, according to the spokesman.

The ministry expects responses early next year to formal requests for information about all four aircraft types in play, the spokesman said. Based on that, officials in mid-2018 will extend invitations to bid to those vendors that make the cut.

“JSF is not a done deal,” said Christian Moelling, an analyst at the Berlin-based think tank German Council on Foreign Relations, using shorthand for the F-35′s other name, Joint Strike Fighter. Moelling argued one big obstacle to an off-the-shelf aircraft from the Americans is that Germany’s industry would see little benefit in such a scenario.