LONDON -- The U.S. Coast Guard has resumed the search for four sailors whose yacht apparently capsized in the mid-Atlantic, after Britain appealed for a renewed effort.

Spokeswoman Lisa Novak said Tuesday that the search for the crew of the Cheeki Rafiki had been re-started "at the request of the British government." Prime Minister David Cameron sent the coast guards his thanks.

The 12-metre high-performance yacht got into trouble on Thursday about 1,000 kilometres east of Cape Cod, Massachusetts while returning to England from a regatta in Antigua. Contact was lost after it diverted to the Azores.

The coast guard, Canadian aircraft and merchant vessels spent more than two days searching for captain Andrew Bridge, 22, and crew members James Male, 23, Steve Warren, 52, and Paul Goslin, 56. The effort was called off Sunday amid treacherous weather.

The suspension of the search caused an uproar in Britain. Almost 200,000 people signed an online petition asking coast guards to keep looking, and families of the missing men appealed to British politicians for help.

"There is every chance that the sailors could be alive either inside the hull of the vessel, or in the life raft," said sailor Ellen MacArthur, who twice broke the world record for the fastest solo circumnavigation of the globe.

James Male's father Graham said the families were "absolutely over the moon" and optimistic they would find out what had happened to the Cheeki Rafiki.

"We have to get some kind of resolution now," he said.