The application made yesterday by Ansbacher Cayman Ltd to the Grand Court of the Cayman Islands sought a direction from the court that the bank should not co-operate with the authorised officer investigating the Ansbacher deposits, Mr Gerard Ryan.

The application was made under the islands' Confidential Relationships (Preservation) Law, which was passed in 1976 and which led to the transformation of the Cayman Islands into a major financial centre. Companies and individuals around the world transferred vast sums of money to the British dependent territory in order to benefit from its secrecy laws.

Under the law, disclosure of confidential information without permission is an offence. The penalty upon conviction is a fine of $5,000 Cayman, or imprisonment for two years. Individuals from banks, accountancy firms and other institutions on the islands are personally liable for any disclosure of information they make.

Confidential information is defined in the law as "information concerning any property which the recipient thereof is not, otherwise than in the normal course of business, authorised by the principal to divulge". The principal is defined as a person who imparted confidential information in the course of a business transaction.

Last year the McCracken Tribunal's legal team travelled to the Cayman Islands as part of their application to have individuals based on the islands give evidence. The individuals were all linked with Ansbacher Cayman.

At the time a spokesman for the bank told The Irish Times: "We will only disclose information if told by the Grand Court to do so. That is the general concept under which the island works." In the event, the court ruled against the tribunal.

The Cayman authorities say their law is designed so it cannot be used to prevent persons being brought to justice. However, getting the Cayman courts to set aside the confidentiality law is notoriously difficult.