The pursuit of EE has become a three-horse race with private equity firms KKR and Apax reportedly reviving their past interest in a joint bid for the UK’s largest operator.

BT is in pole position because it is already in discussion with the UK’s largest operator and Hutchison Whampoa has joined the chase.

And now, according to Reuters, KKR, which is talking to other equity firms, is the third contender. A partnership with Apax is thought likely. The two explored a joint bid for EE in 2012 and 2013.

CVC Capital Partners was part of a rival consortium bidding for EE in 2013 but is not thought to be in the chase this time around.

However, the private equity interest does not extend to O2, which is also in play.

“Any fresh offer hinges on BT’s choice between O2 and EE,” one of the sources said. “EE is the only attractive target for private equity bidders.”

O2 has attracted interested from BT and Hutchison Whampoa.

BT is expected to make a bid for either EE or O2 before Christmas, which would act as a trigger for the private equity players.

In 2013, two groups were thought to be in the running for EE — one led by Apax/KKR and a rival group made up of Blackstone and CVC Capital Partners. The previous year, Apax and KKR were also thought to be interested.

Owners Deutsche Telekom and Orange also considered a partial flotation of EE. In the end, the partners decided to sit tight but might now decide the time is right to sell.