Changes to Council Directive 2003/49/EC of 3 June 2003 on a common system of taxation applicable to interest and royalty payments made between associated companies of different Member States
EU Directive 2003/49
Made by Council Directive 2006/98/EC of 20 November 2006 adapting certain Directives in the field of taxation, by reason of the accession of Bulgaria and Romania
From legislation.gov.uk's record of changes, the official one: see it there.