UK watchdog Ofcom put a halt on a planned spectrum auction until an EC decision on Hutchison 3 UK’s proposed merger with Telefonica’s O2 UK, following complaints from the two companies.

In a statement, the regulator said it had received letters from both objecting to the planned auction of 2.3GHz and 3.4GHz spectrum next year, a process due to commence this month.

Ofcom said both Telefonica UK and Hutchison stated “their intention to bring judicial review proceedings against Ofcom’s decision to commence the auction process before the outcome of the EC’s consideration of the processed merger between those two companies”.

The regulator said it will now not commence the auction process “until the EC has taken its decision” regarding the processed merger, which is “expected no later than mid-May 2016”.

It said it will also wait until a decision is made regarding BT’s proposed £12.5 billion deal to acquire EE, currently being scrutinised by the UK’s competition and markets authority (CMA), although this process is expected to be completed early next year.

Ofcom said it took the initial decision to launch the process before the end of the year because it “recognised the demand for this spectrum and took the view that spectrum efficiency is best achieved by bringing available frequencies into use as soon as possible”.

Objections from both O2 UK and 3 UK are seemingly a representation of a lack of knowledge as to their spectrum requirements going forward, whether or not the deal goes through.

The planned auction, which will see some 190MHz made available in the two bands, is being freed up by the Ministry of Defence, as part of a wider plan to free up public sector spectrum.