The final legal hurdle preventing fresh competitors from entering the mobile phone market should be removed later today when the Supreme Court delivers its judgment on an appeal against the High Court's quashing of the third mobile phone licence award to the US-Irish consortium, Meteor.

The third mobile licence - estimated to be worth millions in potential revenue - was awarded by the regulator in June 1998 following a "beauty contest" between telecoms companies. However, the result was subsequently appealed by Orange, Meteor's rival, to the High Court.

The Supreme Court case is being taken by the director of telecommunications regulation, Ms Etain Doyle, who is seeking to overturn the decision by Ms Justice Macken in the High Court last October.

Ms Justice Macken severely criticised the regulator's office for the way it handled the applications. She said she found the ruling objectively biased and unreasonable.

The regulator's appeal in the Supreme Court was heard in January and February. Legal costs are estimated to have run into millions of pounds and the regulator has set aside some £3.1 million (€3.9 million) from last year's accounts to cover any potential liability following today's decision. It is still unclear whether the eventual winner of a licence may sue for damages from the rival company or the regulator.

Litigation surrounding the third mobile phone award has prevented the entry of a third entrant to the lucrative mobile phone market for over 18 months.

Industry sources estimate this has cost a third operator millions of pounds in lost revenues. It is also not clear how soon a third operator will be able to roll out a network, hire staff and provide a service following today's ruling. This process could take as long as a year.

Consumers have also lost out due to the lack of competition. Recent figures suggest Irish customers pay more for mobile calls than in most other EU countries.

Today's judgment follows on from a settlement reached in separate legal actions taken against the Office of the Director of Telecommunications last week, also concerning the results of a "beauty contest" for a series of broadband and narrow-band licences.

In this case Broadnet Ireland, a company partly owned by businessman Mr Declan Ganley, alleged apparent bias by the regulator in favour of Eircom.