Switzerland’s acquisition of Lockheed Martin F-35A stealth fighters will fall short of its contracted 36 examples due to budget limitations, the nation’s Federal Council has announced.

“Discussions with the United States this summer showed that Switzerland could not impose the contractually agreed fixed price for the F-35A fighter jet,” the European nation’s Federal Department of Defence, Civil Protection and Sport (DDPS) said on 12 December.

The US government attributes this to “additional costs related to inflation, changes in commodity prices and other factors”, it adds.

Approved by a public referendum in September 2022, the Swiss F-35 acquisition is being made alongside an air-defence modernisation activity covering the purchase of Raytheon Patriot and Diehl Defence IRIS-T SLM systems.

The approval capped Bern’s total spend on the fifth-generation fighter at CHF6 billion. That equated to just over $6.2 billion at the time; a figure which has since risen to around $7.5 billion at current exchange rates.

“Due to the foreseeable additional costs, it is not financially viable to maintain the originally planned number of 36 F-35As,” the DDPS says.

Aircraft deliveries are due to be made between 2027 and 2030, according to the original contract schedule.

The Swiss government has not disclosed how many of its intended aircraft can be acquired using its approved funding.

A recently completed review conducted by the Swiss air force’s commander has highlighted the F-35’s importance in boosting interoperability with other European operators of the type, the defence department says.

“In this context, the Federal Council cannot consider giving up the F-35A fighter jet,” it states. “Specifically, the Federal Council has instructed the DDPS to acquire the maximum number of F-35As possible within the financial limits set by the Federal Decree of 15 September 2022.”

Neutral Switzerland is on a path towards spending 1% of its national gross domestic product on defence by 2032. But noting that “the security situation remains tense”, the DDPS says it will “submit target values for the further development of the procedure to strengthen Switzerland’s security and defence” before the end of January 2026.

“Once these issues have been clarified, the Federal Council wants to decide on the possible acquisition of more F-35As in order to reach the planned number of 36,” it says.

Meanwhile, the DDPS points to an eventual need for Switzerland to have a modern fleet totalling between 55 and 70 combat aircraft. “Any possible air asset build-up beyond the already decided acquisition of the F-35A will be considered regardless of the aircraft type,” it says.

The Swiss air force’s current fighter capability is provided by 25 Boeing F/A-18Cs and 15 Northop F-5Es, fleets data from aviation analytics company Cirium shows.