The two companies have signed a letter of intent for Rheinmetall to produce "centre fuselage" parts for the aircraft, the German group said in a statement.

The fuselage is the main body of a plane and the part that normally holds passengers and crew.

If concluded, the deal would represent the first such partnership between the two companies.

"The F-35 centre fuselage production in Germany will be vital to meet the growing global demand for F-35s," said Mike Shoemaker, vice president of F-35 customer programmes at Lockheed Martin.

The F-35 is the world's most advanced warplane, with a shape and low-observability coating that makes it very difficult to detect on radar.

The jet is becoming increasingly popular in NATO and in Europe: Britain, Italy, the Netherlands, Norway and Poland have all placed orders in recent years.

Germany last year signed a deal to buy 35 of the jets to replace its Tornado fleet as part of a military overhaul following Russia's invasion of Ukraine.

However, the success of the F-35 has come at the expense of the French Rafale and the Airbus Eurofighter, as well as casting doubt on a plan to develop a German-French-Spanish next-generation fighter jet known as the Future Combat Air System (FCAS).

Plans for the plane, supposed to replace existing fleets of French Rafales and German and Spanish Eurofighters by 2040, stalled for some time over disagreements between French manufacturer Dassault and competitor Airbus.

But a deal was finally reached late last year and a contract awarded to manufacturers to develop the jet.

German Finance Minister Christian Lindner on Friday welcomed the agreement with Rheinmetall as "a good sign for the transatlantic partnership".

fcz-fec/mfp/rl

RHEINMETALL

AIRBUS GROUP

LOCKHEED MARTIN

DASSAULT AVIATION