A group of Amazon employees said the company threatened to fire them for speaking out about climate change.
Amazon Employees for Climate Justice claim they were told that they were violating company policies by speaking to the press about environmental issues.
In a statement, the group said that tech workers had been contacted by Amazon legal and HR representatives after making public comments about the company's responsibility towards the global climate crisis.
Some workers received follow up emails threatening termination if they continued to speak out about Amazon's business, they added.
"Members of AECJ say Amazon updated its policy about workers speaking to the press and on social media in early September, one day after the group announced they were organising the climate walkout," the statement read.
However, the company said its policy on public comments made by employees is "not new" and covers all of its workers.
An Amazon spokesman said: "We recently updated the policy and related approval process to make it easier for employees to participate in external activities such as speeches, media interviews, and use of the company’s logo.
"As with any company policy, employees may receive a notification from our HR team if we learn of an instance where a policy is not being followed.”
"We understand many of our employees feel passionately about the future of our environment – we do too," the spokesman added, referencing the company's "Climate Pledge" - a commitment to meet the Paris Agreement 10 years early.
Amazon Employees for Climate Justice is a group of the company's workers "who believe it's our responsibility to ensure our business models don't contribute to the climate crisis".
The group has called on Amazon to achieve zero emissions by 2030, limit its work with fossil fuel companies.
It has also urged the firm to stop funding for politicians and lobbyists who deny the existence of climate change.
