PARIS — Norway has narrowed the choice of possible partner countries for its future frigate program to France, Germany, the U.K. and the U.S., and plans to start talks with those countries’ governments about setting up a strategic partnership.

The program to buy at least five and possibly six frigates will represent Norway’s biggest defense investment ever, surpassing the acquisition of F-35 fighter jets, Defence Minister Bjørn Arild Gram said in a briefing on Tuesday. The country plans to make a final decision on a future strategic partner in 2025.

Norway is looking to join an existing frigate program to speed up fielding, thereby obviating upgrade investments in the country’s existing Fridtjof Nansen-class frigates. All major naval forces within NATO are in the process of adding new frigates, and Norway said it wants to establish a strategic partnership with a close ally rather than just buy a stand-alone vessel type.

“The new frigates represent the largest acquisition planned for the Norwegian armed forces in the coming years,” Gram said.

The country plans to invest several hundred billion Norwegian kroner in its navy, as well as significantly increase operating budgets and personnel, according to Gram. One hundred billion kroner is equivalent to around US$9.1 billion.

Norway is an important maritime state within NATO, and the High North is the country’s most strategic area of interest, important to both Norway and the alliance, Gram said. The ambition is for the Royal Norwegian Navy to be able to operate continuously in the ocean areas off Norway, according to the minister.

Defense officials envision a strategic frigate partnership that includes joint acquisition, operation and maintenance, as well as continuous development and upgrades of the ships during their service life. Gram said the new vessels will require upgrade and support for several decades, and Norway is looking for a partner that will commit for the entire service life of the future frigates.

The country isn’t just considering the capabilities of each potential partner country, but also coinciding strategic interests, including in the High North, according to the minister.

France started sea trials of its first Defense and Intervention Frigate this year, with another four ships planned, while Germany laid the keel for the first of four F126 frigates. The U.S. is constructing its first Constellation-class frigate, based on the French-Italian FREMM multi-mission frigate, although that program has run into delays. Meanwhile, the U.K. has seven frigates under construction, including four Type 26 anti-submarine warfare vessels and three Type 31 frigates.

The four countries are working on significantly different-sized vessels, from France’s brand-new FDI frigate displacing 4,500 metric tons, to Germany’s F126 frigate that will displace around 10,000 tons. Norway’s current Fridtjof Nansen-class warships, built by Spain’s Navantia, displace around 5,200 tons fully loaded.

Norway has a longstanding maritime cooperation with France, and while the French have a more global focus than the Norwegians, they’ve shown increasing interest in the High North, the defense minister said. The U.K. and Norway also have particularly close security and defense ties, and the Royal Navy has long been a main partner for the Norwegian forces, according to Gram.

The Nordic country also has security ties with Germany, with cooperation traditionally mainly within the land domain, though the countries are cooperating on submarines and anti-ship missiles, Gram said. Meanwhile, the U.S. is Norway’s most important ally, cooperating in all domains with a focus on the North Atlantic, according to the minister.

A key consideration in the final decision will be the ability for Norwegian technology and industry to contribute to both development and sustainment of the future frigate, according to Gram.

The Norwegian government in 2023 reached out to 11 countries with frigate programs, which in addition to the four nations picked for further talks included Australia, Canada, Denmark, Italy, the Netherlands, Spain and South Korea, according to Gram. The frigate program was included in the country’s long-term defense plan proposed in April.