Rivals Sunrise Communications and Salt Mobile plan to vie for spectrum needed to provide fifth-generation (5G) mobile services in a Swiss auction this month that is also likely to include market leader Swisscom.
Telecoms operators are keen to get 5G spectrum for an edge in new digital services such as powering the Internet of Things, industrial automation and autonomous vehicles.
The Federal Office of Communications (OFCOM) said only that the auction was still scheduled for January and that a result was due by the second quarter of the year.
It provided no other details - not even which or how many companies would take part - for the sale to be conducted by a so-called clock auction.
Potential bidders - which could also include newcomers and foreign groups - are also not allowed to comment in detail, although Sunrise said it had submitted an application dossier and Salt confirmed it was interested in acquiring 5G spectrum.
Swisscom said it would comment only after the auction concluded.
Authorities have said a clock auction ensures bidders can configure frequency packages which best suit their business models. It lets bidders switch between frequency categories in the course of the auction.
The auction covers blocks of frequencies within the 700 MHz, 1400 MHz, 2.6 GHz and 3.5 GHz ranges. It is set to raise at least 220 million Swiss francs ($223 million) if bids are submitted for all the blocks on offer.
Most frequencies are being auctioned off until the end of 2033.
