The Pentagon has denied claims that the U.S. can disable foreign-operated F-35 fighter jets remotely. This follows concerns from Germany, Portugal, and Canada over U.S. control of the aircraft.

“There is no kill switch,” the Joint Program Office (JPO) for the F-35 program stated. “The program operates under well-established agreements that ensure all F-35 operators have the necessary capabilities to sustain and operate their aircraft effectively. The strength of the F-35 program lies in its global partnership, and we remain committed to providing all users with the full functionality and support they require.”

Fears of a so-called “kill switch” have surfaced following reports that the U.S. may have restricted critical targeting data for HIMARS rocket systems in Ukraine. Additional reports also claimed that the U.S.-supplied F-16s stopped functioning in Ukraine after the U.S. announced its decision to pause intelligence aid to the country.

Following reports, officials from two U.S. allies, Portugal and Canada, have stated that their defense ministries are reassessing future fighter jet options in response to evolving geopolitical conditions.

While Lisbon has yet to commit to a next-generation fighter, Ottawa had planned to acquire nearly 90 F-35As from the U.S.

Meanwhile, Germany is set to purchase 35 F-35 Lightning II fighter jets in an €8.3 billion ($9 billion) deal. Despite concerns raised over potential operational restrictions, a source cited by Euronews said that Germany has no plans to cancel the acquisition.

Belgium, the Czech Republic, Denmark, Finland, Greece, Italy, the Netherlands, Norway, Poland, and Switzerland currently operate F-35s in their fleets. Romania also signed an agreement with F-35 maker Lockheed Martin for the aircraft in December.