A women's group has strongly refuted claims that T-shirts sold as part of a pro-feminist campaign were made in a sweatshop.

The Fawcett Society said that evidence it had seen "categorically refutes" the assertion that the 'This is what a feminist looks like' T-shirts produced by Whistles were made under sweatshop conditions in Mauritius.

The group faced claims that women were paid 62p an hour to make the T-shirts, which were worn by Deputy Prime Minister Nick Clegg and Labour leader Ed Miliband.

Labour deputy leader Harriet Harman wearing a feminist T-shirt during Prime Minister's Questions

Labour's deputy leader Harriet Harman wore one in the Commons. The clothes were designed and produced by high street chain Whistles, in collaboration with Elle magazine.

Eva Neitzert, deputy chief executive of the Fawcett Society, said: "We are pleased to confirm that we have today seen expansive and current evidence from Whistles that the CMT factory in Mauritius they used to produce our 'This is what a feminist looks like' T-shirt conforms to ethical standards.

"We have been particularly pleased to receive evidence that 100% of workers are paid above the government-mandated minimum wage and all workers are paid according to their skills and years of service, the standard working week is 45 hours, and workers are compensated (at a higher rate of pay) for any overtime worked, there is a high retention of staff and employees are offered training and development.

"An audit into the CMT factory was carried out in October 2014 by an independent not-for-profit organisation and this did not reveal any material concerns on the working conditions, the welfare or the health and safety of workers, and workers are able to join a union and there is a union presence in the factory.

"The evidence we have seen categorically refutes the assertion that the 'This is what a feminist looks like' T-shirts produced by Whistles were made in a sweatshop.

"Whilst we have confidence in the evidence provided to us, we are currently working closely with an international trade union body to scrutinise it so that we can be absolutely assured of its provenance, authenticity and that all findings are robust and factual.

"Further, whilst Fawcett has a UK remit, we are nonetheless acutely concerned with the inequalities women across the globe face. We recognise that investment in developing countries is vital and support this provided decent labour standards are adhered to.

"We will continue to work with Elle and Whistles on this project."

Since publication of the above Press Association article, The Mail on Sunday has issued the following statement declaring it is standing by its story:

“The Fawcett Society and Whistles claim it has evidence that that factory conforms to ethical standards.

In fact, the statements from the Fawcett Society and Whistles do not contradict a single fact that was published in The Mail on Sunday last weekend following observations, interviews and pictures obtained by our journalists who visited the factory last week.

Workers at the CMT factory in Mauritius are paid 62p per hour and earn the equivalent of one quarter of the country’s average monthly wage.

They sleep in bunk-bed dormitories, 16 to a room.

We spoke to one worker who sends all her money home to Bangladesh and has been too poor to return to see her family for four years.

The president of the International Textile, Garment and Leather Workers Union described these conditions as “sweatshop”.

We are advised that the Government minimum wage in Mauritius is particularly low and that unions prefer to compare salaries to a “living wage” which is more than double the pay offered by CMT.