The development is a follow through on Amazon’s $13 billion acquisition of Whole Foods in 2017.

On Thursday, Amazon.com Inc stated it would start delivering Whole Foods groceries to Prime Now members in select U.S. cities; the service will soon expand to the rest of the country as well.

In a statement, the world’s largest e-commerce retailer stated it will add Whole Foods to its one-hour and two-hour delivery service in Virginia Beach, Austin, Dallas and Cincinnati.

Amazon Prime members will receive two-hour delivery for free and one-hour delivery for $7.99 on orders of $35 or more, said Amazon.

In 2017, Amazon’s $13.7 billion acquisition of Whole Foods was a wake up call to traditional grocery sellers, as they scrambled for ways to deliver fresh, shelf-stable food to consumers at affordable prices.

Wal-Mart, the world’s largest brick and mortar store has also invested heavily in the groceries sector and along with Sprouts Farmers Market, a food supermarket chain, and Kroger Co, a large traditional supermarket operator, has bolstered its delivery system across the U.S.

In 2017, in a first hike in almost 4 years, Amazon raised the monthly fee for its Prime service by $2.