Meteor will initiate an immediate legal challenge if the telecommunications regulator awards the third mobile phone licence to Orange, the company said last night.

But the US-Irish consortium stands ready to supply any updated, supplementary information required, and remains confident of winning the licence.

Mr Brad Horwitz, president of Western Wireless International, the US firm that owns 60 per cent of Meteor, said the consortium would assist the office of the director of telecommunications regulation if it appealed Monday's High Court ruling. Ms Justice Macken found "objective bias" in the decision to grant the licence to Meteor, and ordered the regulator, Ms Etain Doyle, to reconsider the move.

A spokesman for the Minister for Public Enterprise, Ms O'Rourke - who has responsibility for the telecoms sector - declined to comment last night on the latest developments. To do so would be inappropriate, he said.

In an interview with The Irish Times yesterday, Mr Horwitz said Meteor had suffered enormously as a result of the delay. The company had planned to present the Republic's third mobile service last St Patrick's Day, he said. By now, Mr Horwitz added, Meteor would have had at least 40,000 customers and revenues of almost £50 million (€63.5 million).

But he said there was "no chance" Meteor would walk away from the process.

Asked if it would appeal to the High Court as Orange had, if the regulator reversed her decision, Mr Horwitz replied: "Absolutely."

The court case has already taken more than a year, and it would be autumn 2000 at the earliest before a service could be rolled out. If Meteor were to begin a legal action similar to Orange's, further competition would likely be delayed until at least 2002.

"In our view, the tender was clearly written out. It was clear to us what was important - we responded to it clearly, and we won hands down. We had a better overall package.

"It addressed the issues that the regulator wanted, it made the commitments they wanted. It brought a new level of competition to the market, it brought innovation in customer service and distribution - it was a great product," he said. "Will the same plan work now, given where the market is? To a large degree it will," Mr Horwitz added.

Leaving aside the question of an appeal, the judgment leaves the regulator with several options. These would include asking Meteor and Orange to submit supplementary documents to their original bids - effectively adapting their submissions for the changes in the market since last March.

"If that were her decision, we would put together a great package, which reflects how things have changed, and how ready we are - we would make it crystal clear that the first decision was the right decision . . . we are incredibly confident."

Orange said last night it was waiting to see what the regulator would do next and would consider its own response at that point.