Amazon CEO Andy Jassy said on Monday that the company is eliminating 9,000 more positions, just months after a layoff that affected 18,000 employees.

In a blog post, Amazon CEO Andy Jassy wrote that the 9,000 positions are largely in Amazon Web Services, People Experiences and Technology, advertising and at Twitch, its San Francisco-based interactive livestreaming service.

Jassy pinned the layoffs on the uncertain economic environment, writing that the company significantly added to its headcount in recent years.

"However, given the uncertain economy in which we reside, and the uncertainty that exists in the near future, we have chosen to be more streamlined in our costs and headcount," Jassy wrote.

The earlier layoff of 18,000 affected hundreds of workers in San Francisco and Santa Clara counties.