Brussels, Sunday

DIPLOMATS and officials from the European Union and Canada were

working tonight to prevent a violent fish war in the North Atlantic.

After a day of behind-the-scenes exchanges, an EU official said a

meeting could be imminent after a row erupted last week when a Canadian

gunboat fired warning shots over the bows of a Spanish trawler in

international waters and took it into custody.

The EU charged Canada with ''piracy'' and acting illegally while the

Canadian authorities responded that they were merely safeguarding

dwindling fish stocks and that the EU fleet off Newfoundland at the time

was exceeding its quota.

The seized boat, the Estai, was fishing for Greenland halibut 28 miles

outside Canada's 200-mile limit at the time.

Eduardo del Buey, a Canadian foreign affairs department official,

said: ''We're willing to meet the Europeans. I'm sure in the next little

while there will be some signals from one side or the other.''

But the Spanish, often criticised for their record of breaking fishing

quotas, said they would not negotiate until the Estai was released.

Canadian Fisheries Minister Brian Tobin said there was now no sign of

the other EU trawlers -- all Spanish or Portuguese -- in the disputed

area of the Grand Banks known as the Nose and Tail, where Canadian

gunboats continued to patrol.

''Canada has already said it wouldn't negotiate with the Europeans as

long as fishing is going on, but it looks as if the fishing has stopped

now,'' a Canadian fisheries department official said.

The Estai was arrested after Canadian Prime Minister Jean Chretien

personally authorised firing across its bows. He was acting to give

force to a newly-passed Canadian law on fish conservation which is not

recognised by the rest of the world.

The future of this dispute now seems to hinge on how international

lawyers interpret the Canadian action and the Spanish boat's entitlement

to the size of its catch. The EU's case could be weakened if the Spanish

boat is proved to have been overfishing.

John Beck, EU ambassador to Canada, said the matter had to be resolved

by contact. ''It is the only way I can see,'' he said.

* Thousands of angry Newfoundlanders, thrown out of work by the

disappearance of fish stocks, massed today at St John's harbour to

express support for Canada's seizure of the Spanish trawler.

The Estai remained docked in St John's harbour today.