Fortis, part of a consortium led by the Royal Bank of Scotland bidding for ABN Amro, has launched a €2bn ($2.7bn) convertible bond offering to help finance its share of a controversial €71.1bn ($96.5bn) offer for the Dutch bank.

Merrill Lynch and Fortis Bank are bookrunners for the offering, set to close on August 2. The notes will carry a coupon of 3 month Euribor plus 15 to 20 basis points payable every quarter. They will convert to equity in 2010.