Amazon will lay off over 18,000 workers starting January 18 as the e-commerce giant eliminates several roles in an "uncertain economy".

"Between the reductions we made in November and the ones we're sharing today, we plan to eliminate just over 18,000 roles," chief executive Andy Jassy says in a message to employees.

While several teams will be impacted, the majority of job cuts are in Amazon Stores and People, Experience, and Technology (PXT) organisations, the CEO says.

The fresh layoffs come weeks after the Seattle-based online retailer sacked staff across its devices and books businesses. Amazon also announced a voluntary reduction offer for some employees in its People, Experience, and Technology (PXT) organisation.

In a note to employees in November last year, Jassy had said that Amazon will extend firings into the New Year as the company goes through its annual review process to find out ways to cut costs.

"This year's review has been more difficult given the uncertain economy and that we’ve hired rapidly over the last several years," says Jassy, adding that the company is working to support those who are affected and are providing packages that include a separation payment, transitional health insurance benefits, and external job placement support.

"We typically wait to communicate about these outcomes until we can speak with the people who are directly impacted. However, because one of our teammates leaked this information externally, we decided it was better to share this news earlier so you can hear the details directly from me. We intend on communicating with impacted employees (or where applicable in Europe, with employee representative bodies) starting on January 18," the Amazon CEO says.

Amazon has weathered uncertain and difficult economies in the past, and it will continue to do so, Jassy writes. "These changes will help us pursue our long-term opportunities with a stronger cost structure; however, I'm also optimistic that we'll be inventive, resourceful, and scrappy in this time when we're not hiring expansively and eliminating some roles," he says.

"Companies that last a long time go through different phases. They're not in heavy people expansion mode every year. We often talk about our leadership principle Invent and Simplify in the context of creating new products and features. There will continue to be plenty of this across all of the businesses we're pursuing. But, we sometimes overlook the importance of the critical invention, problem-solving, and simplification that go into figuring out what matters most to customers (and the business), adjusting where we spend our resources and time, and finding a way to do more for customers at a lower cost (passing on savings to customers in the process). Both of these types of Invent and Simplify really matter," he adds.

Several big tech firms have announced layoffs in recent months. Social media behemoth Meta sacked 11,000 employees or 13% of its workforce last year. Microblogging platform Twitter, which is now owned by Tesla CEO Elon Musk, sacked over 50% of its workforce. Software major Microsoft fired as many as 1,000 employees, or 1% of its workforce, in the third round of downsising. Snap, the parent company of social media platform Snapchat, sacked 20% of its staff.

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