Extracts of a letter from the French tax authorities dated 11 May, published Monday by French newspaper Le Parisien, reveal that the account assets total more than CHF11bn (£8.7bn, $11.3bn, €10.1bn), “which may represent a several billion euro shortfall for the French Treasury”, the letter said.
According to Le Parisien, the authorities have already identified 4,782 accounts and now want to know the owners of the remaining 40,379.
UBS was ordered by the Swiss Federal Tax Administration to provide account information to French authorities in July. At the time it was not known how many accounts were involved.
“The request concerns a number of UBS account numbers pertaining to current and former French domiciled clients and is based on data from 2006 and 2008,” UBS said in July.
The request from the French tax authorities is based on data received from the German authorities, which have conducted various investigations on tax matters in recent years.
Certain data related to UBS clients booked in Switzerland was seized during these investigations, which appears to have been shared with other European countries.