EE is to launch its own legal challenge against Ofcom's upcoming spectrum auction in a bid to overturn the cap on next-generation 5G airwaves.
BT-owned EE's legal action comes after rival Three also threatened legal action against Ofcom, claiming that Ofcom's caps did not go far enough in preventing companies like EE from dominating the UK's 5G wireless spectrum. EE, in contrast, complains that they are set too low.
But EE, which controls 43 per cent of the spectrum at present, accepts Ofcom's proposed 37 per cent cap for 4G spectrum, it announced over the weekend that it will take action to stop Ofcom from imposing the cap on the 5G spectrum, which is to be auctioned shortly.
This comes just weeks after rival operator Three threatened Ofcom with legal action over the upcoming 5G mobile spectrum auction, arguing that the 37 per cent cap is "meaningless" and doesn't do enough to protect consumers or to maintain a competitive mobile market.
EE claims that the attempt by Three to lower the overall cap will damage its ability to bid in a spectrum auction in 2019 for frequencies used in 5G technology.
EE said in a statement: "In response to Three's action, we have made the difficult decision to challenge the proposed structure of the next auction of mobile spectrum.
"We need to protect our customers' mobile experience, and help build the platform for the UK to have the highest quality 5G networks."
O2 CEO Mark Evans has also waded into the row, and is urging Ofcom to delay plans to auction 5G spectrum, but to press on with its 4G spectrum sale. "What's become clear in the last 24 hours is that the entire industry is aligned that there is no reason this can't go ahead," said Evans.
"The 5G spectrum is contested and it looks like we're going to court, but there is spectrum that can be deployed now. The ball is in Ofcom's court and it is incumbent upon them to act."
He also criticised claims by Three that its court action will cause only a few months of delays to the development of 5G networks, claiming that would only be possible if it loses the case.
Ofcom has yet to comment, but the Financial Times reports that the watchdog has warned that any legal action puts the future of mobile data at risk by potentially delaying the issue of new spectrum and airwaves.
Cotton seedling freezes to death as Chang'e-4 shuts down for the Moon's 14-day lunar night
Fortnite easily out-earns PUBG, Assassin's Creed Odyssey and Red Dead Redemption 2 in 2018
Meteor showers as a service will be visible for about 100 kilometres in all directions
Saturn's rings only formed in the past 100 million years, suggests analysis of Cassini space probe data
New findings contradict conventional belief that Saturn's rings were formed along with the planet about 4.5 billion years ago