What is the difference between accessory and on-demand guarantees?

In case of disagreement between the parties regarding the underlying conditions, payment under an accessory guarantee may be postponed pending amicable agreement, arbitration or final judgement in court. When the beneficiary demands payment in accordance with the terms of a demand guarantee, the bank is obliged to effect payment whether or not the principal is in default under the underlying contract. Any disputes between the principal and the beneficiary must be solved between the parties subsequently without the bank's role. The bank's obligation to pay under the guarantee is based solely on the guarantee itself and is not dependent on the underlying contract.