BERLIN: German lawmakers on Wednesday approved the next phase of a project to build a joint European fighter jet with France and Spain, brushing aside domestic scepticism over the plan.

The budget committee in the Bundestag lower house of parliament gave the green light for the project, known as the Future Combat Air System (FCAS), to progress to research and development phases 1B and 2 between 2021 and 2027.

According to a government document seen by AFP, the next steps in the project are set to cost Germany a total of almost 4.5 billion euros ($5.3 billion).

France and Germany announced plans to build a common fighter in 2017, with Spain joining later.

The plane is slated to replace French-made Rafale jets and German and Spanish Eurofighter planes by 2040.

In Phase 2, France’s Dassault Aviation and European planemaker Airbus are to build a demonstrator aimed at testing the reliability of the jet’s cutting-edge technology.

Dirk Hoke, head of Airbus Defence and Space, welcomed the committee’s vote. “We see this as a strong endorsement and trust in the programme’s ability to develop further European operational and technological sovereignty, whilst strengthening its aerospace industry,” he said on Twitter.

But critics in Germany had warned against hasty approval for the next phase of the project.

Der Spiegel magazine reported in early June that the army’s procurement office had written to the Defence Ministry to say the contract “must be renegotiated from a technical and economic point of view” and was “not ready for signing”.

The deal “almost exclusively satisfies French positions, to the detriment of German industry”, it said.

Dennis Rohde, a lawmaker for the Social Democrats (SPD), said on Wednesday his party still had “many questions” about the project and had demanded “clear conditions for further progress”.