Liberty Global and Vienna Investments are believed to have been shortlisted by Denis O'Brien's Communicorp to buy FM104, the Dublin local radio station.

It is not clear who else remains in the sale process. It is understood that six bids were received for the radio station, including ones from UTV, TV3, UK private equity group Vitruvian Partners and Global Radio, the investment firm that last July acquired Chrysalis Radio, Britain's third-largest commercial radio group.

The shortlisted groups will meet FM104 management - headed by chief executive Tim Fenn - early next week. It is understood that Communicorp hopes to conclude a deal by the end of next week.

Informed sources said the station was likely to fetch between €45 million and €50 million.

FM104 is Dublin's biggest local radio station. It is projected to achieve earnings before interest, tax, depreciation and amortisation of €4.6 million in the year to the end of March 2008. Its total revenues are expected to be €10.6 million.

Liberty Global has emerged as a strong bidder in the process. The Colorado-based listed company owns UPC Ireland, which controls the NTL and Chorus cable television companies.

The company does not have any radio interests as yet. But it has a content subsidiary called Chellomedia, which has invested in a number of television stations in Europe, including David Harvey's Dublin-based City Channel.

Vienna Investments is led by Dermot Hanrahan, a former chief executive of FM104. It includes all of the former shareholders in FM104 before its sale to Scottish Radio Holdings and was a runner-up to Mr O'Brien in the race to buy Emap's three Irish stations - Today FM, Highland Radio and FM104.

Mr O'Brien has agreed to pay €200 million for those stations but is being forced by competition regulators to sell FM104 as he already owns 98FM and Spin 103.8 in Dublin.

It is understood that Mr O'Brien wants to close the radio deal before Christmas.