A new report by the International Monetary Fund has called on member states to set aside the most effective and affordable measures to cope with the crisis.
The report warns that economic policies will not be enough to avoid the worst of the economic fallout from Brexit.
The IMF says that the EU’s policies will “fail to achieve a ‘fair’ return on its current investment, leading to the loss of more than €400 billion a year”.
Brexit’s economic fallout will also cause significant losses to the economy, the report warns, adding that the economic impact of Brexit is likely to be even greater.
The economic fallout is expected to result in the loss, over the next two decades, of more in the region of €1 trillion ($1.1 trillion).
Brexit’s economic consequences will have significant financial costs for the UK as well as for the EU, the IMF warns, with a further £1.3 trillion ($2.2 trillion) likely to have to be taken out of the economy to fund it.
It also says that EU governments will have to set up contingency plans for the economic shock and the potential damage to the EU economy.
A senior EU official told the BBC that the report does not yet give enough detail on how the bloc will deal with Brexit.
The report, titled Brexit: a risk to Europe?
and entitled “An EU response to Brexit: An assessment of the risks”, was compiled by the IMF and the European Commission and was presented on Tuesday.
Brexit is likely in part to be a result of Brexit and the decision by some EU member states, including Italy, Spain and the Netherlands, to leave the EU.
Other EU countries, including France, Austria and Germany, will also be affected by Brexit.