It is uncertain how many companies would be forced close insurance divisions when FSA regulation comes into effect on Friday, reports said today.
The FSA said at the end of December it had authorised more than 10,000 companies to sell or advise on the sale of insurance.
However, it is unknown how many firms have not received authorisation. Reports today said the problem arose with companies for which insurance was an not a key activity.
The FSA said it expects applications to continue coming in until Friday's deadline, but after Friday those trading without authorisation would be breaking the law.