Norway has agreed on a multi-billion euro deal to buy jet fighters from the US defence firm Lockheed Martin, the government announced Thursday.

Norway chose to order an unspecified number of the Joint Strike Fighter (JSF) plane, also known as the F-35, instead of the Swedish-built Gripen jet, which was also under consideration.

"The JSF is the only one of the two candidates to fulfill the operational requirements that the government set out for Norway's new fighter planes," a government statement said.

The JSF order cost six billion kroner (6.7 billion euros, 8.4 billion dollars) less than its Swedish competitor, the Norwegian government said without giving precise figures on the total value of the deal.

Norway wants to replace its ageing fleet of US F-16 warplanes over the next decade.

The Eurofighter consortium, a joint venture between Britain, Germany, Spain, and Italy, pulled out of talks at the start of the year. The group claimed Norway was biased in favour of Lockheed Martin.