(Yicai) June 18 -- Zhang Qing, chief merchandising officer at the China arm of US retailer Sam's Club, has submitted her resignation notice.

Zhang, who is in charge of product procurement, will leave Sam's Club China at the end of this month for personal reasons, parent firm Walmart China announced yesterday. Neil Maffey, who served as CMO from 2013 to 2017 and has been a full-time consultant to the big box retailer since leaving the post, will step in as acting CMO, it added.

The State Administration for Market Regulation recently called in an executive from Walmart China over a series of food safety issues at Sam's Club stores. The SAMR ordered the firm to do business in accordance with Chinese laws and regulations, prioritize food safety, strictly practice corporate social responsibility, prevent risks across the whole supply chain, and safeguard public health, the watchdog said on June 15.

The regulator did not disclose any specific food safety issues at Sam's Club nor the name of the executive.

"As market competition becomes increasingly fierce and rivals start imitating 'bestselling products' created by Sam's Club or its peer Costco Wholesale, it’s becoming more and more difficult for them to provide unique products to their members," a source close to Sam's Club told Yicai.

“At the same time, food safety issues have also begun to emerge from time to time, bringing significant pressure to retailers' procurement and product management,” the person said.

The supply chain of membership stores may get shaken up, the insider pointed out. As product homogenization intensifies, competition is entering a new round of challenges, including how to create distinctive products, appropriately raise the share of imported goods, and ensure food safety, the person said.

Zhang joined Sam's Club in 2017 as vice president and was promoted to senior VP and CMO of the China unit a year later, taking charge of the company's product strategy and procurement management. She contributed to improvements in Sam Club’s brand system in China and the efficiency of supply-chain development.

On the same day that the SAMR made its announcement, corporate registration information showed that Walmart China's chairmanship has been changed to Liu Peng from Muk Sook Yee. Liu joined as president of Sam's Club China last October, having previously worked as an executive at e-commerce giant Alibaba Group Holding.

Editors: Tang Shihua, Martin Kadiev