Planned for several years, the order will enable Oslo to renew its fleet of 36 ageing Leopard 2A4 tanks, some of which are to be donated to Ukraine.

The Leopard 2A7 order with German defence manufacturer Krauss-Maffei Wegmann is part of a 19.7 billion kroner ($1.96 billion) defence allocation already adopted by parliament.

The exact cost of the tanks was not specified. There is an option for 18 more new Leopard 2A7s.

"We find ourselves ... in one of the most difficult security situations since World War II", Prime Minister Jonas Gahr Store told reporters at the Rena military base.

"We have a serious situation due to the Russian invasion (of Ukraine). I call this a new 'Iron Curtain'", he said.

Norway had been hesitating between the latest generation Leopard tank and the South Korean K2 Black Panther.

The choice of Leopards will enable the Scandinavian country to align itself with its Nordic neighbours -- including Sweden and Finland which are vying to join Norway in NATO -- and Germany, the government said.

The first deliveries are expected as of 2026 and will run until 2031.

Only 36 of the 52 Leopards Norway bought from the Netherlands in 2001 are still in service.

Oslo announced in late January that it would donate some of those tanks to Ukraine but did not specify exactly how many nor when they would be delivered.

The head of Norway's armed forces, Eirik Kristoffersen, has previously expressed his opposition to the purchase of new tanks, saying he would prefer to spend the money on the acquisition of other weapons such as missiles and long-range shells.