Wal-Mart has extended its sustainability goals with plans to buy 70% of the products it sells in its US Wal-Mart and Sam's Club stores from suppliers who use its Sustainability Index to share the sustainability of their products.

The Sustainability Index, launched in 2009, is a series of scorecards developed to help buyers evaluate the sustainability of the products they purchase, from raw materials through to disposal.

From 2013, Wal-Mart said it will also use the index to influence the design of its US private brand products.

The world's largest retailer plans to change the way its key global sourcing merchants are evaluated so that sustainability becomes an even more important part of buyers' roles. Beginning in 2013, these buyers will join key buyers in Wal-Mart US and Sam's Club who already have specific sustainability objectives on their annual evaluations.

The retailer's charitable arm, the Wal-Mart Foundation will grant US$2m to fund The Sustainability Consortium (TSC) and assist in its efforts to launch TSC in China. TSC is an independent research organisation, and using the grant, it will engage industries, universities and other experts to form a global network of leaders improving sustainability in consumer goods.

It will also provide tools and resources to help suppliers become more sustainable and competitive. Wal-Mart will use the results of TSC's independent work to refine its Sustainability Index for use in China.

"Today I'm proud to announce a series of steps and commitments that will make Walmart's supply chain, in the United States, here in China, and around the world, more sustainable," said Wal-Mart president and CEO Mike Duke. "The impact of these commitments will be global and make a difference with products sold around the globe."

This broadened implementation of the Sustainability Index was announced at an event in China today (25 October) with government officials, non-governmental organizations (NGOs), academics, suppliers and company associates.