Swiss bank UBS said that it has set aside $4bn to cover potential legal and regulatory costs from its acquisition of Credit Suisse, and that it is expecting to record other asset write-downs.

UBS on 17 May released an updated version of a merger prospectus that was first published three weeks ago. The new document showed that UBS expects to book a $34.8bn gain on negative goodwill, which is when a company acquires assets for less than their worth — typically in a distressed situation.