Britain's most decorated Olympic sailor has told how he has seen "vast areas" of plastic that litter the world's oceans.

Four-time gold medal winner Sir Ben Ainslie, who now heads up an international yachting team, described witnessing large swathes of the sea covered in rubbish.

He was talking to Sky News to support the Sky Ocean Rescue campaign which aims to encourage people not to throw away single-use plastics.

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He told Sky's Dermot Murnaghan: "Out on the oceans there are these five gyros, as they are called, which are collections of plastics in the oceans that the currents bring together.

"They are huge, vast areas of the oceans that are completely covered in plastics and have an impact on the sea life around those key zones.


"And globally, in different seaports, in coastal areas where... eight million metric tonnes of plastics coming in from the land are going into the ocean, that's where the issue lies."

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He said he has been personally affected by what he has seen.

"As someone who is on the sea nearly every day of my life, it's a real issue to my heart, as it is to many others," he added.

"If we do nothing about it, by 2050, there are going to be more plastics in the ocean than there are fish. It's clearly a very real and urgent problem."

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His team, Land Rover BAR, which stands for Ben Ainslie Racing, has been taking action to decrease its impact on the environment.

He said: "We partnered with (a) sustainability organisation... who have really helped us to have sustainability as the DNA of our new America's Cup team.

"We say no to single-use plastics, we have meatless Mondays... at our base in the UK and in Bermuda.

Why should you take part in our campaign?

"Also, we have our... racing exploration zone... that is for young people to come in and to showcase the sustainability initiatives that we have.

"Everyone has to take the responsibility. Going back to single-use plastics and using reusable water bottles, and such initiatives, really will make a difference.

"If businesses, individuals and families can see issues at hand and make some efforts within their lives and in their businesses, then there is a huge potential. It's not too late... to make a difference."

:: You can find out more about Sky Ocean Rescue and get involved by visiting the campaign's website and you can also watch our documentary, A Plastic Tide.