The trust is the latest organisation attempting to cut the number of single-use plastic bags by charging for them or phasing them out all together.

The move comes following a newspaper campaign waging war on the plastic carrier bag, which green groups say damages the environment, and a Government pledge to introduce legislation if retailers did not take action.

Earlier this year, Marks & Spencer announced it was to charge food customers 5p for every plastic bag it gave away, while other companies and charities ranging from Ikea to Help the Aged have taken steps to phase out their use in stores.

Around 13 billion plastic bags are given out free to UK shoppers every year and can take 1,000 years to decay.

Head of commercial operations for the National Trust (NT), Stuart Richards, said: "This is a major step for the National Trust, helping to cut the amount of waste that we generate and encouraging our 3.5 million members and our visitors to use reusable bags."

The trust said the additional income generated by the charge in its 220 shops across England, Wales and Northern Ireland would be used to go towards conservation work and research into climate change impacts.

The NT also said it would be encouraging the use of reusable bags by offering jute bags at a reduced price until July.