The T-shirts, worn by Ed Miliband, Nick Clegg and Harriet Harman proclaiming their feminist credentials, are made by women workers being paid just 62p an hour, according to national newspaper reports.
It is claimed the T-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 the women machinists sleep 16 to a room.
Fashion retailer Whistles, which sells the garments for £45 each, described the allegations as “extremely serious” and said it would be mounting an urgent investigation.
The Fawcett Society’s deputy chief executive, Dr Eva Neitzert, said the charity had been assured by Whistles the T-shirts were produced to “ethical standards”, adding: “If any concrete and verifiable evidence of mistreatment of the garment producers emerges, we will require Whistles to withdraw the range with immediate effect and donate part of the profits to an ethical trading campaigning body.
“Whilst we wish to apologise to all those concerned who may have experienced adverse conditions, we remain confident that we took every practicable and reasonable step to ensure that the range would be ethically produced and await a fuller understanding of the circumstances under which the garments were produced.”
The T-shirts hit the headlines last week when Mr Miliband and Mr Clegg posed in them for photographs for Elle magazine as part of a campaign by the Fawcett Society – which receives all the profits – to promote women’s rights. After David Cameron refused repeated requests to join them, Ms Harman, the Labour deputy leader, then wore one at Prime Minister’s Questions in an attempt to embarrass him.
A spokesman for the Deputy Prime Minister said: “Nick Clegg had no idea where these T-shirts were being made and can only assume that the Fawcett Society were unaware of the origins, or they would not have asked him to wear it. He remains entirely supportive of efforts to ensure all women are treated as equals.”
The Labour Party claimed it was “ happy” to support the campaign to promote feminism.