The product, called Ipsei, is targeted at Europe's growing demand for functional beverages. It contains vitamins and natural antioxidants, and is aimed at the over-30's market.
It is already available in the Netherlands and Germany, and expansion into the UK market could see the product become a global brand. Coke has already applied for a UK trademark.
But while Coke insists that the name is directly derived from the Latin word Ipse meaning 'self,' Pepsi claims that the word sounds suspiciously like 'Pepsi.'
There are reports that the company is thinking about taking legal action. The UK's Financial Times said that Pepsi has already compiled a list of 200 consumers who said that Ipsei reminded them of Pepsi.
The proposed expansion of the Ipsei brand is a big risk for Coca-Cola, which was voted the world's number one brand for the fourth consecutive year in a survey by brand consultancy Interbrand. It is estimated to be worth £39bn.
But it is not all going Coke's way. The company reported an 11 per cent drop in first-quarter profit this year, and experienced growing shareholder unrest at its annual meeting in April.
Coca-Cola reported that it earned $1 billion for the January-March period 2005 compared to a profit of $1.13 billion, for the same period a year ago. Excluding one-time items, Coke said it earned $1.12 billion.
The Atlanta-based giant has had a stressful year. It has had to settle a five-year European Union antitrust case by promising to scrap controversial retail discounts and by agreeing to share more display space with rivals, and had to deal with the discovery of higher than permitted levels of the chemical bromate in samples of its bottled water brand, Dasani in the UK.
The looming dispute with Pepsi over Ipsei is therefore just the latest in a series of obstacles that the world's biggest beverage maker has had to navigate.