Fast-fashion giant Shein spent $600,000 on US lobbying efforts in the second quarter as it continues to face questions from lawmakers about forced labour and its opaque supply chain.Lawmakers from both parties have sent letters to Shein expressing concerns about the company’s potential use of forced labour in the Xinjiang region of China. Further, there are bills pending in Congress that aim to tighten the so-called de minimis loophole, which allows cross-border shippers to avoid scrutiny applied to bulk-import retailers by shipping directly to consumers in packages valued at less than $800.Shein lists Mark Aitken and Sirat Attapit, both former Congressional staffers, as its two in-house registered lobbyists. The most recent spending is in addition to the $230,000 Shein paid to prominent Washington lobbying operations at Akin Gump and Hobart Hallaway & Quayle Ventures in the first quarter.“As a member of the business community, Shein will engage policymakers and participate in discussions that will help us continue to add value to the US economy, support our American workers, and bring industry-wide benefits to consumers,” the company said in an emailed statement.The increase in spending in the period between April and June suggests that the company is gearing up for a protracted fight in Washington as it eyes an initial public offering in the US. To go forward with an IPO, Shein will need to improve its image in Washington, as well as with the general public, amid criticism of the company’s environmental footprint and lack of clarity around its supply chain.The company, which was most recently valued at $66 billion, hasn’t yet filed for an IPO, according to a person familiar with the matter who asked not to be named discussing internal business. That said, investors including Sequoia Capital China, Tiger Global and IDG Capital are seeking to recoup through an IPO the years of investment they’ve put into building Shein.Meanwhile, Shut Down Shein, a separate campaign funded by businesses opposed to the company that operates from the Washington offices of lobbying group Actum LLC, spent $30,000 in the second quarter, down from $90,000 in the beginning of the year.By Olivia Rockeman, Bill AllisonLearn more:Shein’s Years of Explosive Growth Are Over. What’s Next?The fast-fashion retailer has seen sales decline in six of the last seven months, as the novelty of its endless selection of trendy, ultra-cheap clothes wears off.