Amazon announced Wednesday it will cut more than 18,000 jobs from its workforce, citing "the uncertain economy" and the fact the online retail giant had "hired rapidly" during the pandemic.

"Between the reductions we made in November and the ones we're sharing today, we plan to eliminate just over 18,000 roles," said CEO Andy Jassy in a statement to staff. He said that stores operated by the group and human resources would be the main areas affected.

US media had reported in November that the company was planning to lay off 10,000 people. Amazon had said that layoffs were planned but did not give a figure until now.

The job-slashing plan is the largest among recent workforce reductions that have impacted the once-unassailable US tech sector, including at giants such as Facebook-owner Meta.

It is also the largest in Seattle-based Amazon's history.

Jassy said the company's leadership was "deeply aware that these role eliminations are difficult for people, and we don't take these decisions lightly.

"We are 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," he said.

Some of the layoffs would be in Europe, Jassy said, adding that the impacted workers would be informed starting on January 18.

He said the sudden announcement was being made "because one of our teammates leaked this information externally."

"This year's review has been more difficult given the uncertain economy and that we've hired rapidly over the last several years," Jassy said.

But he added that "Amazon has weathered uncertain and difficult economies in the past, and we will continue to do so."

The retailer had gone on a hiring spree during the pandemic to meet an explosion in demand for deliveries, doubling its global staff between the beginning of 2020 and the start of 2022.

The group had 1.54 million employees worldwide at the end of September, not including seasonal workers recruited during periods of increased activity, particularly during the holiday season.