O2 mobile broadband customers have received a download speed boost after the firm made 900MHz radio spectrum available for 3G data connectivity.
Media regulator announced in January that internet service providers (ISPs) would be permitted to use the 900MHz and 1,800MHz radio frequencies for mobile broadband.
This followed a government directive to relax existing restrictions in December 2010, in order to relieve the strain faced by 3G networks as mobile data use increases.
Nigel Purdy, Chief Technology Officer for O2, said the '3G900' switch-on was "the latest in a series of network enhancements for O2".
"We've acted quickly to bring the benefits of 3G over 900MHz spectrum to our customers and we're thrilled with the results.
"Quite simply, on O2's network, more customers can use more data, and experience it quicker."
Mr Purdy claimed the ISP was currently investing the equivalent of £1 million per day into its mobile network infrastructure.