Vodafone has fallen foul of Ofcom's coverage targets, after the mobile regulator ruled the firm has failed to make its 3G services available to 90 per cent of the UK population.
According to Ofcom, Vodafone's coverage fell short by 1.4 per cent, while its rivals EE, Three and O2 all passed with flying colours.
Vodafone has until the end of 2013 to make up the shortfall, which it intends to do by rolling out 3G to a number of additional mobile masts.
Ofcom said it has no plans to take enforcement action against Vodafone at present, but may do if a follow-up review in January 2014 proves unsatisfactory
"Following discussions with Ofcom, Vodafone has put in place a plan to bring itself into compliance with the 3G coverage obligation by the end of 2013," said Ofcom, in a statement.
"Ofcom has reviewed this, and believes it to be credible, but will closely monitor Vodafone's implementation of the plan."
In a statement, Vodafone said it was working on reaching the regulator's target: "Ofcom is fully aware of our plans to ensure compliance by the end of this year.
"Our network investment stands at more than 900m this year alone and we remain on track to deliver indoor coverage across 2G, 3G and 4G to 98 per cent of the population by 2015, two years ahead of the regulator's deadline," it added.
Vodafone, along with EE, Three and O2, was originally given a deadline of 30 June 2013 to comply with Ofcom's 90 per cent UK coverage target.
When the 3G spectrum licences were first awarded in 2000, mobile operators only had to commit to providing 80 per cent of the UK population with access to 3G. This was later revised up, at the behest of the Government, in 2010.
