Liam Byrne, the chair of the British parliamentary committee, has reportedly written to the London Stock Exchange CEO to raise concerns about fast fashion retailer Shein’s planned listing. The letter was written in the wake of last week’s hearing in which Shein’s general counsel for Europe, the Middle East and Africa refused to answer lawmakers’ questions about its supply chain.

In the letter Byrne asks, ‘what checks, if any, has the London Stock Exchange has in place to authenticate statements by firms seeking to list, with particular regard to their safeguards against the use of forced labour in their products.’

Shein’s planned London IPO has faced numerous setbacks as the company battles allegations of labour abuses in its supply chain. Last year, the Swiss-based non-profit group Public Eye found that people employed to produce garments for Shein routinely work more than 70-hour weeks and the company has also been linked to allegations of forced labour in the Uyghur region of China. The British Fashion Council (BFC) has described the planned listing as being of “significant concern” to the industry. In August, Shein itself admitted to discovering two cases of child labour in its supply chain.

In addition to its poor human rights record, Shein’s environmental credentials have also been called into question – the company adds over 2000 products to its website every day and emits 6.3 million tons of carbon dioxide a year in its production processes.

In the US, Shein is currently the subject of RICO charges for allegedly producing, distributing and selling exact copies of designers’ work in what the plaintiffs describe as part of a long and continuous pattern of racketeering, which shows no sign of abating.

Byrne has also written to Britain’s financial regulator, which is in charge of assessing and approving stock market listings asking it how it ensures all legal risks are disclosed prior to an IPO.