Britain will learn this week whether it could be forced to pay up to pounds 30m in damages to Spanish fishermen after trying to ban their boats from British waters in breach of European law.
The advocate general of the European Court of Justice is expected on Thursday to advise the court whether it has the power to hear the long- standing damages claim brought by the Spanish boat-owners. Britain has already been told it had no right to try to stop the Spaniards, who had sought to exploit British fish stocks by registering their boats as British.
A further order that Britain must pay compensation to the Spaniards is likely to fuel animosity between British and Spanish fishermen and harden British attitudes towards the EU's fish quota rules.
The case goes back to 1988 when Spanish boat-owners, seeking to qualify for British fishing quotas, set up front companies and registered their boats as British.
Britain then passed a law preventing foreign-owned boats from registering as British. The Spanish vessels were called into port and tied up. In 1991 the European Court ruled that under single market rules all EU companies should have the right to register in any member state.
British fishermen argued that the ruling made a nonsense of the EU's fish quota system.