The merger of music industry giants Live Nation and Ticketmaster will now fall under scrutiny from Britain's fair trading watchdog after the deal was referred to the U.K.'s Competition Commission.

Plans for the concert promoter and the ticketing website to join forces were put into place earlier this year (Feb09).

The merger would create an industry superforce in a deal estimated to be worth a staggering $575 million (£396 million), and has been backed by musicians including Seal, Shakira and Eddie Van Halen.

But despite Ticketmaster's lenders giving the deal the green light in May (09), the move is still under review by the U.S.'s Subcommittee on Antitrust, Competition Policy and Consumer Rights.

Now, executives from both companies must also justify the case to the U.K's Office of Fair Trading, over fears the merger could monopolise the ticketing and concert industry.

The Competition Commission will issue a ruling on the case by November (09), which comes as a blow for both companies, who expected the full deal to be completed by the autumn (09).