UK high street retailer Marks & Spencer is to change the care labels on almost three-quarters of its clothing ranges in a bid to encourage customers to lower washing temperatures to 30°C.

The changes announced by the retailer today (23 April) are part of a campaign led by The Climate Group which brings together businesses, government, non-government organisations to help UK households reduce their carbon emissions.

They also boost the green credentials of M&S, which earlier this year launched "Plan A", a GBP200m eco-plan that includes the use of recycled plastic bottles to make its polyester clothing and increasing the number of Fairtrade cotton garments on sale in its stores.

Chief executive Stuart Rose said encouraging our customers to wash their clothing at 30°C "is a small change, but it can make a very big difference."

"It's not only effective on around 70% of M&S garments, but it's also economical and better for the environment - saving around 40% of energy on each wash.

"If we all moved to washing at 30°C we could save enough electricity to light every street lamp in the UK for 10 months."

The new care labels will include the words 'Think Climate - Wash at 30°C', and advice will also be provided through in-store leaflets and décor, advertising and on the company's website.

Research conducted by YouGov for Marks & Spencer shows that climate change is a major concern for the majority of people in the UK with a third believing it to be the biggest challenge facing the world today.

73% say they have changed the way they behave in the last 12 months in response to concerns about the environment and nearly 60% believe that individuals should be ultimately responsible for tackling climate change.

Last year a survey by the University of Cambridge suggested that transport accounted for 15% of the energy used in shipping cotton to China from America, making it up into a T-shirt then moving it to Europe - but that buying and using the T-shirt used nearly ten times as much energy as transport.

Washing a T-shirt at 40ºC rather than 60ºC reduced total energy use by 8%; but drying it on a hanger and not ironing it reduced energy use by half, the Cambridge survey found.