Coca-Cola is doubling the amount of recycled plastic in its British drinks bottles to 50%, the company has announced.
All 20 of Coca-Cola drinks brands in the UK (including Sprite, Fanta, Smartwater and Schweppes) will move from 25% recycled plastic in their bottles to 50% by 2020.
The increase will involve a new deal with Clean Tech, which operates Europe's largest plastic bottle reprocessing plant, in Lincolnshire, and see Coca-Cola sourcing all of the recycled plastic it uses from within Britain.
Once bottles have been collected and recycled they will return to shop shelves as part of new packs in as little as six weeks, the company said.
But further changes are needed to the UK recycling system to boost the availability of high quality recycled plastic, it said.
The move to boost the recycled content of plastic bottles is part of a new sustainable packaging strategy by the company.
It also includes investing in marketing and advertising to promote recycling, supporting well-designed measures such as deposit-return schemes and testing an on-the-go bottle recovery and reward programme.
The soft drinks giant has been the target of a global campaign by Greenpeace urging it to ditch "throwaway plastic", as part of the environmental group's push against plastic pollution in the ocean.
Millions of tonnes of plastics are ending up in the ocean every year, harming marine wildlife, taking centuries to break down and spreading toxic chemicals, Greenpeace says.
Jon Woods, general manager of Coca-Cola Great Britain, said: "Our packaging is valuable to us and we don't want to see any of it end up where it shouldn't.
"All of our bottles and cans have been 100% recyclable for some time now, so in theory none should be littered. But we know that isn't happening and that's why we are going to do more.
"Doubling the amount of recycled material in all of our plastic bottles is a significant investment and sends a clear signal that we want to play a positive role in supporting the circular economy here in Great Britain.
"In the strategy we have focused on the actions we can take as a business - such as our ability to communicate to consumers the importance of recycling - as well as the areas where we want to work in close collaboration with others to reduce litter and increase the recovery and recycling of plastic bottles."
Marcus Gover, chief executive of waste reduction body Wrap, said: "To have a brand as well-known and with the reach of Coca-Cola actively encouraging more people to recycle is a really positive step which we welcome.
"A commitment that half of all the plastic bottles they use will be recycled plastic, understanding that this will cost the business more, shows real leadership in the industry and provides the essential market for recovered materials."
Louise Edge, Greenpeace UK oceans campaigner, said people expected companies such as Coca-Cola to make their bottles out of 100% recycled plastic.
She questioned how the drinks giant would reduce the "sheer scale" of plastic it was pumping out globally.