Guinness Red, on which Diageo has confirmed it is working, has a different flavour from the original. Made from lightly-roasted barley, it is also ruby-red
in colour, rather than the black of its parent brand, but it retains its trademark white head.
It will be trialled in a few pubs during the coming months to measure demand before off-trade plans are devised.
A spokeswoman for the company said: "As you would expect, Diageo is continually monitoring the market and talking to consumer and commercial partners to help us identify new opportunities."
Three Guinness variants are currently available in the UK and the company is testing a mid-strength brew in Ireland. Separately, Diageo has also recently trialled an Irish bottled cider brand, Cashel's Extra Smooth, in selected English pubs.