NEW YORK, United States — Neiman Marcus is working with Lazard on the sale of luxury apparel platform MyTheresa, which may fetch more than €500 million ($560 million), people familiar with the matter said.

Neiman said on Tuesday that it was evaluating options for MyTheresa, which has been at the centre of a dispute with creditors since the unit was effectively transferred out of bondholders’ reach in September. The firm has been working with Lazard and law firm Kirkland & Ellis LLP to help address its debt load.

The move to sell the fast-growing German unit comes as the US company is working on cleaning up its debt-plagued balance sheet. The department-store operator hasn’t made any final decisions on a specific transaction or time frame for reviewing the unit, Neiman said in a filing. Representatives for Lazard and Neiman declined to comment.

Interest in the online luxury retail sector has surged in the last few years as brands use online portals to attract the increasing numbers of customers who choose to shop on the web. Farfetch shares have gained 24 percent since the high-end shopping platform listed in September.

Private equity firm Apax Partners in 2017 agreed to buy UK-based online luxury fashion boutique Matchesfashion.com. Sky News reported that Apax agreed to pay £800 million for a controlling stake in the company, citing sources it didn’t name.

Neiman isn't giving up on online luxury retail. Last month, it bought a minority stake in Fashionphile, an e-commerce company focused on pre-owned handbags and accessories.

By: Eyk Henning; Editors: Kenneth Wong, Amy Thomson, Anne Riley Moffat