Wal-Mart Stores Inc's (WMT.N: Quote, Profile, Research) Sam's Club warehouse division said on Wednesday it is limiting sales of several types of rice, the latest sign that fears of a rice shortage are rippling around the world.

Sam's Club, the No. 2 U.S. warehouse club operator, said it is limiting sales of Jasmine, Basmati and long grain white rice "due to recent supply and demand trends."

U.S. rice futures hitting an all-time high Wednesday on worries about supply shortages.

On Tuesday, Costco Wholesale Corp (COST.O: Quote, Profile, Research), the largest U.S. warehouse club operator, said it has seen increased demand for items like rice and flour as customers, worried about global food shortages and rising prices, stock up.

Sam's Club, the No. 2 U.S. warehouse club operator, is limiting sales of the 20-pound (9 kg), bulk bags of rice to four bags per customer per visit, and is working with suppliers to ensure the products remain in stock.

Warehouse clubs cater to individual shoppers as well as small businesses and restaurant owners looking to buy cheaper, bulk goods.