The Federal Trade Commission, whose new chairwoman has been critical of Amazon.com, will review the company's planned purchase of MGM, a source familiar with the matter said.
Amazon said in May that it would buy the U.S. movie studio, home to the James Bond franchise, in an $8.45 billion deal that would give it a huge library of films and TV shows to compete with streaming rivals led by Netflix and Disney+.
The Wall Street Journal was the first to report that the FTC would review the deal.
Lina Khan was sworn in as FTC chair on June 15 in what was broadly seen as a victory for progressives seeking tougher antitrust enforcement.
In 2017, Khan wrote a highly regarded article, "Amazon's Antitrust Paradox," for the Yale Law Journal. It said the traditional antitrust focus on price was inadequate to identify antitrust harms done by Amazon.
The FTC also has an antitrust probe open into Amazon, and has reviewed other mergers that the company has done. The agency shares the work of merger enforcement with the Justice Department.
The source was unauthorised to speak to the press on the matter and asked for anonymity.