Grocery outlets are facing even more competition after Amazon decided to give its food delivery service free for Amazon Prime users.

The services are free around 2,000 cities across the U.S. and London. They will also serve one and two-house delivery choices and include choices from Whole Foods. Current prime members who already get the $14.99 delivery service will get access to the service for free, while interested members will have to be invited. Orders over a minimum order threshold will be eligible for free two-hour delivery for Prime members and quicker delivery options will be available for additional fees.

Walmart

Shares of megaretailer Walmart were down 1.1% after rival Amazon announced that it was getting rid of the monthly fee tied to its Amazon Fresh grocery delivery service.