请大家帮我分析一下这个案例
Bishop Ltd in Country M contracted with Roofer Ltd in Country P to purchase 50,000 grade 1 slate roofing tiles. The contract states that the CISG will apply. In order to make payment under the contract Bishop Ltd secured a letter of credit from My Bank in Country M that names Roofer Ltd as the beneficiary. The letter of credit requires that a bill of lading naming My Bank as the consignee; the export documentation from Country P; a certificate of authenticity as to the quality of the slate; and the import tax clearances from Country M must be presented in order to collect payment under the letter of credit. The letter of credit states it is subject to the
UCP 600. When Roofer Ltd placed crates containing the tiles aboard a carrier for shipment, it received a bill of lading for 50,000 roofing tiles and the export documentation from Country P. At the half way point of the journey, the carrier is caught in the middle of a violent storm and 2,000 tiles are lost over board. When the remaining 48,000 tiles are delivered 5,000 are found to have been damaged in the storm. A further 3,000 are discovered to be of grade 3 quality not grade 1.
Bishop Ltd contacted My Bank and demanded that they not pay on the letter of credit and has told Roofer Ltd that it will not be accepting delivery of the tiles. Meanwhile Roofer Ltd has presented the export documentation from Country P, the customs documentation from Country M and the bill of lading to My Bank and is demanding payment from My Bank under the letter of credit. My Bank is stating that it is not required to make payment.
Bishop Ltd comes to you for advice as to whether it can stop My Bank paying Roofer Ltd under the letter of credit and what its obligations are under the contract.
用ucp600和CISG哪个条款可以解答！谢谢
