Celebrities including Joanna Lumley, Dominic West and Paul Whitehouse have accused fast food giant Nando's of 'killing' British rivers.

The celebrities, who also include Jo Brand and Hugh Fearnley Whittingstall, are calling on the restaurant giant to clean up its supply chain and tackle its contribution to severe river pollution in an open letter.

The River Wye, in Herefordshire, is highly polluted by manure flowing into its rivers from millions of factory-farmed chickens in the area.

The group - claim that Nandos' suppliers are part of this environmental disaster and have written an open letter to Nando's CEO Mark Standish backed by environmental groups River Action, The Rivers Trust, Friends of the Wye, and the Angling Trust,

The letter states: 'Nando's is a British icon-which is exactly why we need to talk. Your chicken is killing our rivers. The Wye used to be one of Britain's most beautiful rivers.

'Now? It's turning into a brown, lifeless mess - killing wildlife, destroying habitats, and even making local children sick after swimming. The culprit? 

'Pollution from factory farms that supply chicken to major restaurant chains like you. This is where your responsibility lies as CEO of Nando's.'

The letter is calling on the restaurant chain to design and put in place a plan to protect Britain's rivers.

Nando's has 1,200 restaurants in 30 countries worldwide. The UK is its biggest market. 

The letter continues: 'You are buying chickens from massive factory farms and their waste is absolutely destroying Britain's rivers. 

'The good news is that you've got the power to help fix this. Nando's isn't the only company buying these chickens - but as one of Britain's most-loved brands, when you make moves, others follow.'

BBC presenter and naturalist Chris Packham, another signatory said, 'If Nando's wants to position itself as a sustainable and ethical company, it cannot ignore the environmental catastrophe in its supply chain. The Wye is dying, and companies profiting from its destruction must take responsibility.'

River Action's head of campaigns Amy Fairman said, 'The Wye River is on the brink of ecological collapse, and companies like Nando's have a moral responsibility to ensure their supply chains are not driving this destruction.'

Their open letter urges the company to honour its advertised values and take meaningful responsibility for its supply chain's impact.

The letter accuses the group of stating on its web page that Nando's supplier 'assures' the restaurant group it's 'not spreading waste on chicken farms in the area. But where's the proof it's not ending up in our rivers'.

Phosphorous pollution in the Wye has led to algae blooms and the river turning green on occasions.

Nando's said in a statement: 'We care passionately about the environment and having a positive impact. We have a water policy in place for all our chicken suppliers. We will meet with River Action and we are happy to discuss with them how this might be further improved. We are not polluting the River Wye, and our supplier has assured us that no manure is spread, stored or otherwise disposed of on any of the chicken farms we source from. We will be conducting an independent third-party audit to provide further assurances.'