English to Spanish Bus/Financial Finance (general) Cuentas anuales

En este párrafo aparece el término "reliance letters" y no encuentro ningún término equivalente en castellano. Aquí va el contexto:

the due diligence reports issued by the Lenders’ Legal Counsel, the Independent Technical Engineer, the Lenders’ Tax Advisor, the Model Auditor and the Insurance Advisor in form and substance satisfactory to the Lenders, together with reliance letters addressed to the Finance Parties

Muchas gracias por adelantado