Eircom shares have fallen heavily in Dublin and London for a third successive day.

The stock closed at €2.58 (£2.03) last night, dropping 19 cents in the session, driven down by fears that critical talks with Vodafone over the €5.1 billion sale of Eircell have started to unravel.

The shares are now 17 cents below the €2.75 level they were at when the Vodafone talks became public. The company is valued at €6.1 billion, just €1 billion more than Vodafone was reported to be prepared to pay for Eircell. Eircom was not helped by general weakness in telecoms and technology stocks across Europe.

A number of significant stumbling blocks have emerged in recent weeks, delaying the Eircell deal which was originally to have been concluded in the middle of November.

Eircom delayed publication of its interim results in the hope that the deal could be announced at the same time. Although the company does not technically have to publish the figures until the end of December, it should have produced them before the end of November in order to comply with industry practice.

The absence of any firm date for the interims and, as a result, no up-to-date information about the company is further undermining the stock price.

Among the issues to be resolved between Eircom and Vodafone is the relationship between Eircom and its former subsidiary once the deal is complete. Vodafone wants to ensure that Eircom, or its future owners, do not start to compete directly with it in the mobile market and, more specifically, do not seek a third generation mobile licence.