International Chamber of Commerce Brochure No. 222. ” Article 3 of the brochure says that:
” An irrevocable credit is a definite undertaking on the part of an issuing bank and constitutes the engagement of that bank to the beneficiary or, as the case may be, to the beneficiary and bona fide holders of drafts drawn and/or documents presented thereunder, that the provisions for payment, acceptance or negotiation contained in the credit will be duly fulfilled, provided that all the terms and conditions of the credit are complied with.
An irrevocable credit may be advised to a beneficiary through another bank without engagement on the part of that other bank (the advising bank), but when an issuing bank authorises another bank to confirm its irrevocable credit and the latter does so, such confirmation constitutes a definite undertaking on the part of the confirming bank either that the provisions for payment or acceptance will be duly fulfilled or, in the case of a credit available by negotiation of drafts, that the confirming bank will negotiate drafts without recourse to drawer.
Such undertakings can neither be modified nor cancelled without the agreement of all concerned. “
The scope of an irrevocable letter of credit is explained thus in Halsbury’s Laws of England (volume 34, paragraph 319, at page 185):
” It is often made a condition of a mercantile contract that the buyer shall pay for the goods by means of a confirmed credit, and it is then the duty of the buyer to procure his bank, known as the issuing or originating bank, to issue an irrevocable credit in favour of the seller by which the bank undertakes to the seller, either directly or through another bank in the seller’s country known as the correspondent or negotiating bank, to accept drafts drawn upon it for the price of the goods, against tender by the seller of the shipping documents. The contractual relationship between the issuing bank and the buyer is defined by the terms of the agreement between them under which the letter opening the credit is issued ; and as between the seller and the bank, the issue of the credit duly notified to the seller creates a new contractual nexus and renders the bank directly liable to the seller to pay the purchase price or to accept the bill of exchange upon tender of the documents. The contract thus created between the seller and the bank is separate from, although ancillary to, the original contract between the buyer and the seller, by reason of the bank’s undertaking to the seller, which is absolute. Thus the bank is not entitled to rely upon the terms of the contract between the buyer and the seller which might permit the buyer to reject the goods and to refuse payment therefore ; and, conversely, the buyer is not entitled to an injunction restraining the seller from dealing with the letter of credit if the goods are defective. “
 Chalmers on Bills of Exchange explains the legal position in these words:
” The modern commercial credit serves to interpose between a buyer and seller a third person of unquestioned solvency, almost invariably a banker of international repute ; the banker on the instructions of the buyer issues the letter of credit and thereby undertakes to act as paymaster upon the seller performing the conditions set out in it. A letter of credit may be in any one of a number of specialised forms and contains the undertaking of the banker to honour all bills of exchange drawn thereunder. It can hardly be over-emphasised that the banker is not bound or entitled to honour such bills of exchange unless they, and such accompanying documents as may be required thereunder, are in exact compliance with the terms of the credit. Such documents must be scrutinised with meticulous care, the maxim de minimis non curat lex cannot be invoked where payment is made by the letter of credit. If the seller has complied with the terms of the letter of credit, however, there is an absolute obligation upon the banker to pay irrespective of any disputes there may be between the buyer and the seller as to whether the goods are up to contract or not. “
Similar are the views expressed in Practice and Law of Banking by H.B. Sheldon, the Law of Bankers’ Commercial Credits by H.C. Gutteridge, the Law Relating to Commercial Letters of Credit by A.G. Davis, the Law Relating to Bankers’ Letters of Credit by B.C. Mitra and in several other text books read to us by Mr. Mohan Kumaramangalam, learned counsel for the Russian firm. The legal position as set out above was not controverted by Mr. M.C. Setalvad, learned counsel for the Indian firm. So far as the Bank of India is concerned it admitted its liability to honour the letter of credit and expressed its willingness to abide by its terms. It took the same position before the High Court.