Jason Buechel will expand his role to oversee Amazon’s Worldwide Grocery Stores business, including Amazon Go convenience stores and Amazon Fresh physical and online stores, while also continuing to serve as Whole Foods Market CEO.

In his expanded role, Buechel will oversee Amazon's roster of grocers, including Whole Foods, Amazon Fresh, Amazon Go and other grocery partnerships, as the division looks for ways to boost revenue. He will keep his role as CEO of Austin-based Whole Foods.

Whole Foods workers in Philadelphia became the first group to unionize under the grocery store chain. The vote came months after it filed to hold a union election in November.