The Office of the Director of Telecommunications Regulation (ODTR) last night stood by its decision to grant the third mobile licence to Meteor, and said it was prepared to argue its case with vigour.

In a statement, the office headed by Ms Etain Doyle described the High Court challenge by Orange as "a procedural matter".

"The ODTR will, if necessary, defend its position resolutely. Orange has been informed that it was ranked second in the competition, and has been given the fullest possible written and oral feedback on the evaluation of its bid," Ms Doyle said in a statement.

The evaluation was conducted precisely in line with the terms of the tender documentation and Orange's application had been made in accordance with that documentation, she said.

"The evaluation was carried out on exactly the same terms for both applicants," the statement continued.

Industry analysts say that at the heart of the regulator's preference for Meteor was a commitment by the company to broaden the customer base for mobile phones, and drive down tariffs. Orange's presentation is believed to have focused more on high-end users' technological advances.

Meteor is a consortium made up of the US-based Western Wireless International, which holds 60 per cent; the Irish-owned RF Communications with 30 per cent; and the US Walter Group consultancy. Western Wireless, a subsidiary of Western Wireless Corporation, has 645,000 mobile phone subscribers in the US and holds licences in Latvia, Georgia, Ghana and Iceland.

Orange is Britain's third-largest mobile phone operator, and is involved in licences or applications in several other European countries. Its shareholders are Hutchinson Whampoa, which owns 49 per cent; British Aerospace, with 5 per cent; and the remainder held publicly.

A spokeswoman for Meteor said last night the company had from the start of the licensing process remained confident in the regulator, was satisfied with her decision to grant it the licence, and was sure the decision would be upheld.