Royal Mail broke competition law when it tried to change the way it charged rivals such as Whistl for use of its network, according to provisional findings by regulator Ofcom.
Whistl complained to Ofcom after the changes were announced in January last year, prompting an investigation. Royal Mail suspended the move in March 2014 and said that it had withdrawn the planned changes in March this year.
Ofcom said its provisional view was that Royal Mail “breached competition law by engaging in conduct that amounted to unlawful discrimination against postal operators competing with Royal Mail in delivery”.
Royal Mail vowed to submit a “robust defence” to the watchdog and said it considered that the changes it had planned were “fully compliant with competition law”.
Ofcom has the power to fine the group up to 10 per cent of its annual turnover. Revenues for the year to the end of March totalled £9.3 billion.
Dutch-owned Whistl, formerly known as TNT, suspended deliveries in May after private equity backer LDC pulled out of funding to help it expand.