UK Accountant letter to confirm nature of business

Recently incorporated company and wanting to open bank account. The bank is asking for a letter from accountant signed and confirming the nature of business.

I can provide with a filled out template of accounts certificate (if needed) plus all documents you need so that you only have to review and sign. Shoestring funds hence the budget. Hopefully not too much trouble for somebody to sign.

Must be UK qualified accountant.