The Swiss Air Force announced on Friday it has accepted five bids for a new fighter aircraft as part of Switzerland’s air power modernization effort named Air2030. European firms Airbus, Dassault, and Saab all placed bids, as did U.S. firms Boeing and Lockheed Martin. The Swiss Air Force currently operates both the Boeing McDonnell Douglas F/A-18C and D models, as well as the Northrop F-5 Tiger, according to a report from Reuters.

“The phase of analysis and testing starts,” read a statement from the Swiss Defense Department. “From February to March 2019, specialists from (Swiss defense procurement agency) armasuisse and the Swiss Air Force will test the aircraft in simulators.”

The aircraft competing are Airbus’s Eurofighter, Boeing’s F/A-18 Super Hornet, Dassault’s Rafale, Lockheed Martin’s F-35A Lightning II, and the Gripen E made by Saab. Late last year, Belgium chose the F-35 over the Eurofighter after deciding on the two finalists. Both Saab and Boeing initially submitted bids but ended up pulling out of the negotiations, according to a report from Defense News. The decision came in the face of intense pressure from Belgium’s allies to choose the Eurofighter, which is currently operated by Britain, Germany, Italy, and Spain, according to Reuters.

“The F-35 offers transformational capability for the Belgian Air Force and, if selected, will align them with a global coalition operating the world’s most advanced aircraft,” said Lockheed Martin’s Mike Friedman, communications manager for the F-35 program in an email, according to Defense News. “The F-35 program is built on strong international partnerships, and our proposal includes significant industrial opportunities for Belgian companies to contribute to the global F-35 enterprise.”

Unlike Belgium, however, Switzerland is not part of the North Atlantic Treaty Organization (NATO) and thus enjoys more autonomy when it comes to defense spending. Sweden, home of Saab and the Gripen E, is also a non-NATO member. However, the Gripen E was already voted down in 2014 by the Swiss parliament. Still, Sweden is offering the Swiss government several perks to sweeten the Gripen deal, including a “100% offset package for Swiss industry,” in exchange for ordering at least 30 of the Saab fighters, according to Janes.

Saab is also looking to sell the Gripen outside of Europe. According to one report from Business Standard, the company is actively submitting proposals to sell nearly 100 of the fighters to the Indian Air Force. The deal, worth around $20 billion, also includes provisions to have the Gripen built in India.