Elon Musk has had a busy Friday on Twitter. After flatly denying that he has ever spoken to Apple CEO Tim Cook in response to a wild story alleging he demanded to take over as the company’s CEO as part of an acquisition offer, Musk has now tweeted his support of Epic Games’ fight against Apple over App Store policies.

“Apple app store fees are a de facto global tax on the Internet,” he said. “Epic is right.”

Epic is currently embroiled in a legal battle with Apple, arguing that its App Store rules, which allow Apple to take a 30 percent commission on many transactions on the App Store, are unfair and anti-competitive.

Perhaps aiming to take advantage of the massive spotlight Musk is bringing to the fight by tweeting about it to his 58.7 million followers, CEO Tim Sweeney, who has been a vocal opponent of Apple on Twitter, posted his latest salvo against the iPhone maker just 25 minutes after Musk’s tweet. “In the future all physical goods will have a digital presence, and Apple will tax and gatekeep world commerce,” Sweeney said. “Apple must be stopped.”

Apple has not replied to a request for comment. Epic pointed The Verge to Sweeney’s tweet.

Epic faced off with Apple in court for much of the month of May, and while we’re still awaiting a verdict on the lawsuit, the trial itself revealed all sorts of interesting information. Epic has also filed an antitrust suit against Google over Play Store policies, though that case is moving more slowly.

Update July 30th, 3:28PM ET: Added that Epic pointed us to Sweeney’s tweet.