“The German Council of Economic Experts calls for constructive negotiations to prevent an exit, or at the least to come to an agreement that minimizes the damage on both sides,” the experts wrote in their annual report.
Chancellor Angela Merkel is to receive a copy of the report on Wednesday.
“Due to the consequences, political actors should not assume too soon that the Brexit is a done deal,” the German economists advise.
At the same time they warn that “a stance which is too lenient could encourage others to become copycats, with unforeseeable consequences.”
The economist group says though that the short-term economic impact on Germany will be moderate and the country is in a strong enough position to cope with it.
Long-term it is the UK which will suffer most under the split from the rest of Europe, they warn.