U.S. senators have previously slammed Live Nation's lack of transparency and inability to block bot purchases of tickets following a major fiasco involving ticket sales for Taylor Swift's long-awaited concert tour in late 2022.

Antitrust officials investigating the company have been frustrated with Ticketmaster over how slowly it has responded to the DOJ's requests, the Bloomberg report said on Monday, citing people familiar with the probe.

The DOJ had earlier planned to file an antitrust lawsuit against Live Nation Entertainment and Ticketmaster by the end of 2023, according to a media report last July.

Instead, the DOJ opted to extend its investigation and potentially file a case later this year, the Bloomberg report added.

Ticketmaster and the world's largest concert promoter, Live Nation, completed their merger in 2010 after agreeing with U.S. antitrust officials to divest some assets.

Live Nation, Ticketmaster and the DOJ didn't immediately respond to a Reuters request for comment.

(Reporting by Kanjyik Ghosh; Editing by Sherry Jacob-Phillips)