Bank guarantee requirement ensures unconditional, irrevocable on-demand payment securing fulfilment of authorisation obligations. Appendix 25A prescribes an unconditional, irrevocable bank guarantee payable on demand to secure losses to the Government arising from breach of an import/export Authorisation, including failure to meet export obligations; a demand by the Government is conclusive and payable despite disputes. The guarantee is continuing, not revocable without Government consent, remains enforceable until the Licensing authority certifies discharge or the prescribed claim period lapses, and is unaffected by variations, extensions, forbearance, or changes in the constitution of parties.