Private equity firm Sycamore Partners has indicated it is interested in purchasing troubled US apparel retailer Express Inc.

In a letter to the company's board, Sycamore, which has amassed 9.9% stake in the business, said it would like to perform due diligence on the firm to determine a price for the retailer.

Express acknowledged receipt of the letter and said it has now established a special committee of the board to determine a course of action it believes is in the best interest of all its stockholders.

The company has also adopted a stockholder rights plan, which is intended to "ensure all stockholders realise the long-term value of their investment in the company" and protect them from "unfair or coercive takeover attempts". It will also provide the board with sufficient time to consider any and all alternatives to an offer.

Last month, Express outlined a cost-reduction plan designed to save US$18m per year and close 50 stores, after reporting an 84.3% drop in first-quarter profit.

Sycamore's investment portfolio includes Aeropostale, MGF Sourcing, Nine West Holdings, TalbotsHot Topic, Jones New York and Kurt Geiger. The private equity firm most recently said it would relaunch troubled women's wear retailer Coldwater Creek as an independent company after acquiring the brand and other intellectual property.