By Arriana McLymore

(Reuters) - Amazon (AMZN) is ramping up its speedy delivery service by offering 1-hour and 3-hour shipping in ‌markets across the U.S., including Los Angeles and Chicago, in ‌its latest efforts to stave off e-commerce competition from its biggest rival Walmart (WMT).

Fast delivery has been ​a significant part of Amazon's push to increase basket sizes and shopping frequency. The company in December announced a separate service called "Amazon Now" to deliver grocery items and everyday essentials in 30 minutes or less in select locations including ‌Seattle and Philadelphia.

"We saw ⁠an opportunity to use our unique operational expertise and delivery network to help make customers’ lives a little easier while ⁠unlocking even more value for Prime members,” Amazon Senior Vice President of Worldwide Operations Udit Madan said in a press release.

The Seattle-based e-commerce giant said on Tuesday that its 1-hour delivery ​option ​is available on more than 90,000 products, ​including everyday essentials, toys and ‌toilet paper, and will rely on its existing same-day delivery network. The 60-minute option has launched in major U.S. metropolitan areas and smaller cities like Boise, Idaho. The 3-hour option has launched in more than 2,000 cities and towns. Perishable groceries are available in select areas, Amazon said.

To ensure the ‌1-hour and 3-hour orders are fulfilled in ​a shorter amount of time, Amazon introduced designated ​work stations for these orders ​within existing same-day delivery centers, new yellow labels that are ‌placed on the packages for easy ​identification and updated ​signage throughout the site to easily direct delivery partners, the company said.

Using the high-speed delivery comes at an extra fee. Prime members pay ​an extra $9.99 for 1-hour ‌delivery and $4.99 for 3-hour delivery. Shoppers without Prime memberships pay $19.99 for ​1-hour orders and $14.99 for 3-hour deliveries.

(Reporting by Arriana McLymore in New ​York City; Editing by Stephen Coates)

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