Apple did not confirm the billionaire's allegations but it is not an unusual move by the tech company as it previously banned Gab and Parler applications.
Elon Musk has accused Apple Inc of threatening to block Twitter Inc from its app store without saying why in a series of tweets that also said the iPhone maker had stopped advertising on the social media platform.
The billionaire CEO of Twitter and Tesla said on Monday Apple was pressuring Twitter over content moderation demands.
The action, unconfirmed by Apple, would not be unusual as the company has routinely enforced its rules and previously removed apps such as Gab and Parler.
Parler, which is popular with US conservatives, was restored by Apple in 2021 after the app updated its content and moderation practices, the companies said at the time.
"Apple has mostly stopped advertising on Twitter. Do they hate free speech in America?," Musk, who took Twitter private for $44 billion last month, said in a tweet.
He later tagged Apple Chief Executive Officer Tim Cook's Twitter account in another tweet, asking "what's going on here?"
Apple did not immediately respond to requests for comment.
"It wasn't clear to me how far up the Apple food chain that idea went internally and without knowing that, it isn't clear how seriously to take any of this," said Randal Picker, a professor at the University of Chicago Law School.
The world's most valuable firm spent an estimated $131,600 on Twitter ads between November 10 and November 16, down from $220,800 between October 16 and October 22, the week before Musk closed the Twitter deal, according to ad measurement firm Pathmatics.
Apple has also threatened to withhold Twitter from its App Store, but won’t tell us why— Elon Musk (@elonmusk) November 28, 2022
'Go to war'
Among the list of grievances tweeted by Musk was the up to 30 percent fee Apple charges software developers for in-app purchases, with Musk posting a meme suggesting he was willing to "go to war" with Apple rather than paying the commission.
The fee has drawn criticism and lawsuits from companies such as Epic Games, the maker of 'Fortnite', while attracting the scrutiny of regulators globally.
The commission could weigh on Musk's attempts to boost subscription revenue at Twitter, in part to make up for the exodus of advertisers over content moderation concerns.
Companies from General Mills Inc to luxury automaker Audi of America have stopped or paused advertising on Twitter since the acquisition, and Musk said earlier this month that the company had seen a "massive" drop in revenue.
Free speech chart
Twitter will "soon" publish documents that Elon Musk alleged on Monday will chronicle efforts to stymie free speech.
"The Twitter Files on free speech suppression soon to be published on Twitter itself. The public deserves to know what really happened …" Musk tweeted without elaborating.
Musk did not resolve the ambiguity of whether the documents are about Twitter's internal affairs, or if they will simply be published on the platform.
Teams that had traditionally been used to monitor compliance with Twitter's internal rules have been decimated, prompting several advertisers to halt their operations on the website, including Jeep and Mars Candy, according to the Washington Post newspaper.