Countries across Europe have been alarmed by US President Donald Trump casting doubt on future transatlantic ties.

On Thursday, the Sueddeutsche Zeitung daily reported that German Defence Minister Boris Pistorius was planning to consult with top military officials over security issues related to the jets and other US-made systems.

However, on Friday, defence ministry spokesman Mitko Mueller told reporters: "No 'crisis meeting' is planned, not today, not in the future. We are continuing with the project."

In the wake of Russia's full-scale invasion of Ukraine in 2022 Germany said it would buy 35 of the jets to replace its ageing Tornado fleet.

Concerns have been raised that Washington could potentially exercise control over the jets, including via a potential "kill switch" embedded in the aircraft, giving Washington the final say over any use.

However, Mueller insisted that "there is no way to simply 'switch off' the F-35s remotely".

Experts have warned that even in the absence of such a "switch", the jets would be reliant on spare parts and software updates and could transmit data to the United States.

Earlier this month, Canada -- which Trump has said should be the "51st state" in the US -- said it was reviewing its own plans to purchase F-35 jets.

Mueller pointed out that the jet is "not an exclusively American product".

"It was developed by eight countries, 14 NATO member states use it or will use it soon... this community of different users plays an important role," he said.

Chancellor-in-waiting Friedrich Merz has said he wants European suppliers to have priority for future defence contracts.

However, in the case of replacing the Tornados, the F-35s are considered the best fit for carrying US nuclear warheads stationed in Germany.