Explained: The Nordic countries’ secret action plan for times of crisis

“Our assessment is that if something happens in our part of Europe, everyone is affected in some way,” Swedish Defence Minister Peter Hultqvist told public broadcaster SVT after the meeting in Stockholm.

Recent world events, most notably Russia's attacks on Georgia in 2008, annexation of Crimea in 2014 and the conflict in eastern Ukraine, are thought to have worsened the security situation in the Nordics.

Sweden is the current chair of Nordefco (Nordic defence cooperation) and hosted representatives from Denmark, Finland, Iceland and Norway this week.

One of the top items on their agenda was a so-called 'crisis consultation mechanism', which would, in the event of emergency, be triggered by the defence ministry and would act as a supportive mechanism for the Nordic governments.

Special high-security rooms are now being set up in each defence ministry, with telephones and equipment for video calls that would be encrypted.

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“This is built on [the requirement that] we can quickly connect with each other and have an encrypted, classified information link between the countries to be used in different situations when we think it is necessary in a crisis situation, but also in other situations where we judge that it is needed,” Hultqvist told the TT news agency.

This means it wouldn't only be important in the event of war, but also in situations such as the heatwave and wildfires of 2018.

Other examples Hultqvist gave of events where the crisis mechanism would be used were if military and civil aircrafts were affected by GPS problems, or “provocative behaviour” from foreign armies such as when Russia in 2013 simulated large-scale attacks on Sweden.

The countries have already tested out the setup and practised run-throughs of different situations.