Walmart is taking on Amazon, launching a new membership service that includes free shipping (if you spend at least $35). Those grocery robots had better be ready.

Announced Tuesday and launching Sept. 15, the long-rumored Walmart+ offers unlimited free delivery for customers along with fuel discounts of up to 5 cents a gallon, and other in-store and online benefits to come.

Walmart+ will cost $12.95 a month or $98 per year — in comparison, Amazon Prime costs $12.99 a month or $119 a year, and includes access to its streaming service, Prime Video. Importantly, however, Walmart+ members will have to spend at least $35 to qualify for free delivery, whereas Amazon Prime has no minimum spend.

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SEE ALSO:What it would take for a big box chain like Walmart to go package-free

As we suspected, it's not a completely new offering for the U.S. retail giant — Walmart has basically spruced up its existing subscription service called Delivery Unlimited, which did exactly that, allowing customers an unlimited number of deliveries for an annual or monthly fee. These members will be automatically switched over to Walmart+. Walmart already does free curbside pickup, and next-day or two-day delivery for a price.

"Walmart+ will bring together a comprehensive set of benefits where we see the greatest needs from our customers and where our scale can bring solutions at an unprecedented value," said Walmart's chief customer officer, Janey Whiteside, in a press statement.

It's a busy time for Walmart, and not just within its 4,700 stores across America. The news comes just days after reports that the company is possibly teaming up with Microsoft to acquire TikTok.