AEG, which has assets including The O2 London, Hammersmith Apollo and the contract for concerts in Hyde Park, took over the contract to manage Wembley late last year.

The Hyde Park and Wembley contracts had previously been held by arch-rival Live Nation, which has recently announced it will now stage its London outdoor events at the Olympic Stadium site.

In the middle of January, the UK’s Office Of Fair Trading confirmed it was looking into AEG taking over at Wembley Arena, and considering whether it should recommend that the Competition Commision look at the deal.

On March 22 the OFT said it has referred the matter to the CC “due to concerns the merger may substantially reduce competition in the live entertainment venue sector.”

It said the Wembley deal means that AEG now operates the two largest London indoor venues, the other being The O2 arena.

OFT senior director Jackie Holland said the deal would result in a major consolidation of the indoor spaces where large concerts, sports and other shows can be held in the capital and may result in higher costs for promoters to hire suitable venues, which ultimately may be passed on to consumers in the form of higher ticket prices.

“As such, we believe it is appropriate that the Competition Commission reviews this merger in detail to ensure that the interests of consumers are protected,” she said.

AEG was put up for sale late last year by billionaire Philip Anschutz with a $10 billion price tag, but that turned out to be too high for would-be bidders and its since been taken off the block.