Several firms have submitted initial bids for a majority stake in RT╔'s broadcast transmission network, in the first stage of a process which should be completed before the end of the year.

It is believed that most of the bidders were international corporations and private equity groups rather than Irish-based telecoms and media firms. Potential bidders for the network include France Telecom, Apax Partners, Crown Castle, Merill Lynch, American Tower, and the US company, Spectra Site. Several of these firms did not return calls last night. NTL, ESB, Eircell and Chorus, who had previously expressed an interest in acquiring the network, confirmed to The Irish Times yesterday they had not entered the bidding contest.

Industry sources said the broadcasting network- which incorporates 130 masts throughout the State- would probably be sold for between £40-50 million.

This is towards the lower end of previous valuations suggested by RT╔, which initially claimed its network would be worth up to £70 million.

This valuation may have been impacted by the downturn in the technology sector and a one year delay in the sell off process, according to experts.

The delay was caused by differences over RT╔'s proposed shareholding in the new network company which will be created following the sale.

Initially, the Minister for Arts, Heritage, Gaeltacht and the Islands proposed that RT╔ retain a 40 per cent shareholding in the new firm. This was subsequently amended to 28 per cent.

Neither RT╔ nor its corporate advisers, UK finance house N M Rothschilds & Sons, would comment yesterday on the identities of the bidders. In a statement RT╔ said the bidders included leading operators in the transmission and tower management industries as well as private equity firms.