Debris found in the area of the Atlantic Ocean where UK yacht the Cheeki Rafiki went missing does not belong to the stricken vessel, the US Coast Guard has said.
The crew of a catamaran reported seeing a plank and a piece of foam in the search area.
But the US Coast Guard has now ruled out any connection with the British boat.
First Coast Guard District Chief of Response Captain Anthony Popiel said: "Our search assets have found a variety of debris and trash during their searches. The key part is correlating these objects to the search effort.
"We take reports of debris very seriously and, at this time, no debris or objects reported during this search correlate to the Cheeki Rafiki. This is still a very remote region of the Atlantic and our search planning is focused on directing the US and international military ships and aircraft we have deployed. We are also working directly with volunteer commercial ships in the area."
The search for the missing crew was resumed on Tuesday afternoon following a public outcry, but despite combing 12,000 square miles of ocean, rescue teams have had no sighting of the life raft.
Relatives of the men said the operation was being boosted by additional air support and seven aircraft would be searching for the 40ft yacht.
The British sailors got into trouble as they were sailing back to the UK from an Antigua regatta and started taking on water 620 miles east of Cape Cod, Massachusetts, last Thursday.
The four men on board – experienced captain Andrew Bridge, 22, from Farnham in Surrey, and crew members James Male, 23, from Southampton, Steve Warren, 52, from Bridgwater, Somerset, and Paul Goslin, 56, from West Camel, Somerset – have not been seen or heard from since the early hours of Friday morning.
Relatives of all four men met Foreign Office officials in London today.
Graham Male, father of James, said: "It was a very constructive meeting, it really filled the families in with the detail. What we can say is the UK Government and the US Coast Guard are right behind us, which we're so grateful for.
"We know there's going to be some resources going out there. Of course it's a large area to cover. They are going to continue their support."
Cressida Goslin, wife of Paul, said three US military aircraft will join the search, alongside two Canadian planes, one from Britain and one from the US Coast Guard.
She added: "We're very pleased, it's wonderful news. I don't think anybody could be doing anything more than they are."
Hugh Robertson, minister for North America, said: "I have just had a second meeting with the families of the missing yachtsmen in the Atlantic. The UK Government remains in constant contact with our US colleagues and I was able to update them on the continuing search.
"I'd like to thank the US Coastguard for their significant efforts thus far, and to assure everybody that the UK Government will continue to do everything possible to try and locate these missing yachtsmen."
The sailors' families are in discussions with a crowd-sourcing initiative set up by a satellite company. Tomnod, run by DigitalGlobe, allows people to view satellite photos online and tag objects of interest. It was previously used following Typhoon Haiyan and the disappearance of Malaysian Airlines flight MH370.
Mr Warren's daughter, Laura Carpenter, said: "It's a free website so you just sign up and then you can search images and you can tag if you see anything, then they send the co-ordinates to the coastguard or the yachts that are out there."
She said she hoped the system would be set up soon but acknowledged that it was a lengthy procedure.
Gloria Hamlet, Mr Warren's partner, remained hopeful the men would be found.
"If there's eyes out there looking for them then there's a chance," she said. "Hopefully today will be the day but we've got to wait and see.
"At the end of the day we're trying to be very grounded and trying to be very realistic, but you can't help but hope."
During yesterday's meeting with Foreign Office and American embassy officials, the families presented the US ambassador with letters thanking President Obama and the US Coast Guard for restarting the search for their loved ones.