I referred earlier to an unusual requirement of the agreement which at Article 15.5 makes provision for the flag state, instead of seeking surrender of the detained vessel and crew, to request the intervening state to release them forthwith without charge. When such request is made, the intervening state is obliged to release them. Provision for this requirement is made in section 21(d) of the Bill. In drawing up the agreement, the experts felt that it would be difficult to foresee all the kinds of situations that might arise in its practical operation. It was, therefore, agreed to include this provision as an exceptional safety valve in case something went entirely wrong in the procedure. The explanatory report with the agreement makes it clear however that this provision would only be relied upon in very exceptional circumstances.