Spain's top diplomat has urged Canada to resume its search for the bodies of 12 sailors missing, presumed drowned, after one of its fishing trawlers sank off Newfoundland.

There were 24 people onboard the vessel when it went down off the eastern coast of Canada early on Tuesday. Rescuers pulled three survivors to safety and later found nine bodies.

Canadian rescuers called off the hunt at 2000 GMT on Wednesday after an "exhaustive" 36-hour operation in difficult weather conditions, in which they combed 900 square nautical miles (around 3,090 square kilometres).

Speaking to Onda Cero radio, Foreign Minister Jose Manuel Albares said he had asked his Canadian counterpart, Melanie Joly, for the searches to resume when the weather eased.

"What I conveyed to her - and she wanted the same thing - was the desire that as soon as weather conditions allow, the search efforts will continue in so far as possible," he said, recalling the conditions in which the operation was suspended.

"Waves of more than eight metres (26 feet), very low visibility, temperatures of -3 degrees Celsius, making it practically impossible to continue the search and even endangering the lives of the rescue teams."

Pope sends message to families

The Villa de Pitanxo, a freezer trawler based in the northwestern region of Galicia, sank in bad weather some 250 nautical miles east of Newfoundland, in what was Spain's worst fishing tragedy in nearly 40 years.

Onboard were 16 Spaniards, five Peruvians and three Ghanaians. Only three crew members survived - two Spaniards and a Ghanaian.

Given the freezing water temperatures and the rough seas, there is practically no chance of finding any more survivors.

But family members have begged the authorities not to give up the search, if only so they can bury the bodies of their loved ones.

On Friday, Pope Francis sent his "heartfelt sympathy and solidarity (with the families) in such a moment of suffering".

Spain will hold an official day of mourning for the shipwreck victims on Monday, government spokeswoman Isabel Rodriguez told reporters after Friday's cabinet meeting.

She said a boat carrying two of the victims' bodies would reach Newfoundland in the coming hours, while a second vessel carrying the other seven bodies and the three survivors would land on Saturday morning.