Department store retailer Sears Holdings has opened up its website to third-party sellers, including competitors, as part of a new online mall called Sears Marketplace.

Sears' move, which was first announced on just-style in September, mirrors one taken by Wal-Mart Stores Inc around the same time, and means a wider selection of products will be available to customers in one convenient location.

In fact, Sears says over 10m products from more than 1500 sellers are now available via Sears.com, including clothing and footwear.

"We believe that by providing customers with more products to choose from, along with the ability to compare offers for the same item across other sellers, our customers will be better informed to make the best decision for themselves," said Imran Jooma, senior vice president for Online at Sears Holdings.

"We understand our customers are time-starved and value-focused and we believe Marketplace at Sears.com addresses those everyday concerns."

The new online store will also help merchants expand their company's online visibility, and products from JC Penney, Neiman Marcus, Dillard's and other department stores are already listed on the site. Retailers like Banana Republic, Old Navy and Boden also have products on show.

Sellers can either choose to drive traffic to their own websites through a Cost-Per-Click business model, which ranges from $0.60 for shoes to $0.30 for workwear and uniforms. Fitness & Sports categories will be charged at $0.70 - $0.90 per click.

Alternatively, the Fulfilled-by-Merchant model lets items show up on Sears.com and be purchased through its checkout process.

The merchant will pay Sears a monthly fee and commission for the service, and will manage and support the order, including shipping and handling, customer service, exchanges and return.

The move is thought to have been prompted by weak sales at Sears, which operates its namesake and Kmart stores.