Apple Inc and Amazon.com Inc have suspended Parler from their respective App Store and web hosting service, saying the social networking service popular with many right-leaning social media users has not taken adequate measures to prevent the spread of posts inciting violence.
The action by Apple and Amazon follows a similar move by Alphabet Inc's Google on Friday. Parler is favored by many supporters of U.S. President Donald Trump, who was permanently suspended from Twitter on Friday, and it is seen as a haven for people expelled from Twitter.
"We have suspended Parler from the App Store until they resolve these issues," Apple said in a statement Saturday.
Apple had given Parler 24 hours to submit a detailed moderation plan, pointing to participants' using the service to coordinate Wednesday's siege of the U.S. Capitol.
Amazon's move effectively takes the site offline unless it can find a new company to host its services.
Amazon suspended Parler from its Amazon Web Services (AWS) unit, for violating AWS's terms of services by failing to effectively deal with a steady increase in violent content, according to an email by an AWS Trust and Safety team to Parler, seen by Reuters.
An Amazon spokesperson confirmed the letter was authentic.
Due to the "very real risk to public safety" that Parler poses, AWS plans to suspend Parler's account effective Sunday, at 11:59 p.m. PST, the email seen by Reuters showed.
Parler Chief Executive John Matze lashed out at Amazon, Google and Apple, saying it was a coordinated effort knowing Parler's options would be limited and it would inflict the most damage right as Trump was banned from other social media platforms.
"There is the possibility Parler will be unavailable on internet for up to a week as we rebuild from scratch," he said in a post on Parler.
"This was a coordinated attack by the tech giants to kill competition in the market place... You can expect the war on competition and free speech to continue, but don't count us out."
In addition to Parler, right-leaning social media users in the United States have flocked to messaging app Telegram and hands-off social site Gab, citing the more aggressive policing of political comments on mainstream platforms such as Twitter Inc and Facebook Inc.