It was the first time since the 1990s that such a large-scale drill had been carried out involving royals, the armed forces and various officials, the government said.

With tensions high following Russia's invasion of Ukraine, Prime Minister Ulf Kristersson said in the statement that the drill had been held "in light of the present security situation.

"Step by step and exercise by exercise, we are strengthening Sweden's total defence and resilience," he added.

The exercise focussed on "measures to maintain Sweden's security" in a "scenario involving war and the risk of war".

The statement was followed by a Russian-language translation of the text.

Sweden's intelligence and defence services cite Russia as the main threat to the country.

Stockholm has accelerated its military spending since the invasion of Ukraine and its accession to NATO in 2024.

It plans to allocate $32 billion to defence over the next decade.