The US Federal Communications Commission pledged to spend $54.6 billion on spectrum from TV broadcasters, as part of the process of freeing up radio frequencies for mobile broadband.

The figure is a fall of 37 per cent from the first-round sum of $86.4 billion the regulator said it would spend on airwaves held by broadcasters back in June, pointed out The Wall Street Journal.

The fall is likely the result of the FCC buying fewer frequencies, and paying less for what it acquired, said the report. Now the regulator must try to offload the spectrum to mobile operators (and any other bidders).

In June, operators were dubious about spending on frequencies at the higher price. Bidders, thought to include AT&T and Verizon, offered to pay $23.1 billion, although bidders’ identity remain anonymous until the process is complete.

Now it is the FCC’s second attempt to match the expectations of the broadcasters about what their frequencies are worth, and what the operators are willing to pay.

For the sale to work this time around, operators (and any other bidders) must dig into their pockets to cover the $54.6 billion, plus a further near-$2 billion in transition and administrative costs. Bidding will resume next week (19 October).