However, Daniel Berger, captain of the Swiss armoured brigade, sought to play down the specificity of the threat.
"The exercise has strictly nothing to do with France, which we appreciate" he told the Swiss press. "It was prepared in 2012, when fiscal relations between both countries were less tense." "French towns were cited to provide soldiers with a real scale," he said.
Famous for its bank secrecy laws, Switzerland often comes under criticism for allowing foreign account holders to hide their wealth from tax officials at home.
But these opaque laws are coming under increasing fire as France and the US, among others, are cracking down on tax evasion during a period of economic hardship.
This is by no means the first imaginary scenario dreamed up by the Swiss army. Last year, it carried out an exercise based on the premise that a huge wave of refugees crossed into the country after the implosion of the European Single Currency and ensuing chaos across the continent.
"Stabilo Due" centered around a risk map created in 2010 and envisaged internal unrest between warring factions as well as the possibility of refugees from Greece, Spain, Italy, France, and Portugal.
Warning of an escalation of violence in Europe, defense minister Ueli Maurer said at the time: "I can't exclude that in the coming years we may need the army." The military is a hot topic in Switzerland, which has mandatory military service. Under Swiss law, all able-bodied men at age 19 have to undergo five months of training, followed by refresher courses of several weeks over the next decade.
A referendum held a week ago saw a large majority of Swiss voters reject plans to abolish conscription.
The current number of recruits stands at around 155, 000 the biggest army in Europe relative to population size.
Some 73.2 per cent of Swiss said "no" to proposals by the anti-military group, Group for a Switzerland Without an Army, to have either a professional army or one made up of volunteers.
Neutral Switzerland has not been invaded since the Napoleonic Wars of the early 19th century.
Recent scholars have questioned the belief that the Swiss military's complex of underground bunkers deterred an invasion by the Nazis during the Second World War.
Some historians argued that Adolf Hitler left the Swiss alone because he wanted to use their banks.