There are several issues in The UCP 600 Rules in Letter of Credit which is, Principle of autonomy (article 5), All Credit is Irrevocable (Article 3), Strict Compliances (Article 14(D), (E), (J), Article 18(C)), Notice of Refusal (Article 16) and Fraud in Letter of Credit. What is the issue and what is the relations of the issues between legal rules and principles of laws that applicable to particular business transaction crossing national boards? Explain with cases examples.