The next season of the programme, which is shown on RTE and hosted by Irish broadcasting institution Gay Byrne, was due to start again in the autumn. 'Who Wants to be a Millionaire' regularly attracts audiences of more than 700,000.
However, it has emerged that it may be off screens until the new year at best and be off the air for good if a new sponsor is not found to replace Irish mobile phone operator Eircell.
Eircell, now part of Vodafone, paid around €8.25m (£5.36m) to sponsor the programme as part of a two-year deal in July 2000, making it one of the biggest sponsorship deals in Irish television history.
'Who Wants to be a Millionaire?' in the UK makes a fortune from its premium-rate phone line entrance fee, with a large population to entice with the promise of a huge cash prize.
However, with a population of only 3.8m and a comparatively high exchange rate, the Irish premium-rate phone line has never generated enough money to cover production costs.
RTE is said to be in negotiations with several potential sponsors.
No contestant is yet to win the €1m jackpot in Ireland. However, the Irish edition of 'Millionaire' did make history by being the first in the world to see a contestant leave the programme without even winning the lowest prize.
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