A women's rights charity behind a T-shirt campaign is investigating claims by the Mail on Sunday that the products were made in sweatshop conditions.

The Fawcett Society has said it will have the clothes withdrawn from sale if the reports are proved true. The Mail alleged that the T-shirts, worn by Ed Miliband, Nick Clegg and Harriet Harman proclaiming their feminist credentials, are made by female workers being paid just 62p an hour.

The paper said its investigation found the shirts with the slogan "This is what a feminist looks like" were being produced on a factory on the Indian Ocean island of Mauritius where female machinists sleep 16 to a room.