By Sean Carney

PRAGUE--The Czech telecommunications regulator, or CTU, Monday said it has set new parameters for an auction of mobile radio frequencies that could lead to a fourth cellular operator entering the local market.

"The goal is to support the development of high-speed mobile internet networks of the fourth generation, intensify competition, support the entrance of a new mobile operator and improve the quality of mobile services," the CTU said.

The period of consulting with potential bidders will last through May 8, the regulator said, adding that in June it will likely announce the deadline for interested parties to submit offers.

The regulator now expects bids to be below 10 billion koruna ($505.5 million).

The CTU last month suspended an earlier version of this auction when bids climbed to above CZK20 billion, or nearly three-fold of the minimum bid of CZK7.4 billion set at the start of the auction.

Such high sums would force operators to recoup investment by increasing costs to end-users, which runs against the goals of the competition, the regulator said.

The CTU said it will now offer 800 megahertz frequencies, the most lucrative of available bandwidths, exclusively to new operators to boost competitiveness on the market, which is now dominated by three operators: the local units of Telefonica SA (TEF), of Deutsche Telekom AG (DTE.XE) and of Vodafone Group PLC (VOD).

The bandwidth auction aims to speed up the roll-out of new high-speed mobile networks with long-term evolution technology, or LTE, the successor to third-generation, or 3G, mobile data services.

Write to Sean Carney at sean.carney@wsj.com

Go to http://blogs.wsj.com/emergingeurope/ for the WSJ blog on Central and Eastern Europe, covering business, politics, society and more, written by our correspondents across the region.

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