One of Germany’s best known and respected think tanks has found the five billion euro cost of closing Europe’s borders is just a “fraction” of the cost associated with leaving them open and experiencing continued mass migration.

The Munich-based Institute for Economic Research (Ifo) has released new figures quantifying what exactly the damage to the German and European economies would be, and it is significantly lower than previous estimates. Taking into consideration the inconvenience and delays to trade introduced by taking action at Europe’s borders to prevent illegal migrant incursion, the Ifo put the figure at €5 billion a year.

Although a significant amount of money, report author Gabriel Felbermayr said “this cost represents only a fraction of the burden which would be incurred by continuing unregulated mass migration”. By way of comparison the cost of reception and initial care of refugees was estimated to hit €20 billion a year for just Germany alone, reports Die Welt.

This figure excludes the costs associated with migrant crime and other societal costs, and does nothing to even consider the long term costs of mass migration. A recent report from a Stockholm University academic into the life-long costs of mass migration found just the 2015 arrivals in Sweden would cost around 600 billion Swedish crowns, around £50 billion, a figure professor Jan Tullberg called “conservative”.

The cost was estimated to be roughly the same as 14 years worth of Swedish defence budgets.

The new €5 billion cost figure by the Ifo is significantly lower than numbers produced by think-tank France Stratégie, which suggested the cost could be hundreds of billions. The methodology of that report has been questioned and the findings said to be “clearly exaggerated”, as they calculated costs based on all European internal borders being closed even in places where they clearly did not have to be. Luxembourg, Portugal and Spain were included in the border closure study, although they don’t sit on migratory routes.

The suggestion that borders are more cost effective than mass migration echoes calls by an Austrian politician from 2015, who said of the migration crisis that border fences are “cheaper than illegal mass immigration”. Freedom Party of Austria (FPÖ) Heinz Christian Strache was demonised in the press at the time for calling for border defences but has since been vindicated.