"Three years ago, if you mentioned the term ‘securitisation' people immediately assumed you were referring to lending that was secured against trade receivables," says William Cummings, managing director at Citigroup in London.

Since then, landmark transactions, dubbed whole-business securitisations, such as the £1.7bn (€2.4bn) Welsh Water (Glas Cymru) deal in 2001, have blurred the definition. He says: "Glas was a hybrid deal. It was where the securitisation world met the corporate lending world. It bridged the gap between the two because you had a single transaction issuing both bonds and loans out of the same asset-backed financing."