Sir Terry Wogan has suggested that he may quit as the BBC's voice of the Eurovision Song Contest because he does not wish to preside “over yet another debacle” that has nothing to do with the quality of the songs.

He announced live on air on Saturday night that he and his producer would have to “decide whether we want to do this again” after Russia won in a highly political event in Belgrade. Andy Abraham, the British contestant, finished in joint last place.

Sir Terry, 69, who has been a commentator for the competition since the 1970s, said that he would “have to wait and see” whether he felt inclined to return to the contest when it takes place in Moscow next year.

He predicted that Britain would always come last regardless of the quality of its entries because there is no British diaspora living in other European countries to sway the voting. “It has never been much of a music contest,” he said last night. “It has always been an event, but at least the voting used to be about the songs. Now it's really about national prejudices.”

He said that the Balkans and the Scandinavians could be relied upon to vote for one another and that Russia had a huge advantage because of its neighbours being prepared to lend their support. “I think the British music industry and the BBC really have to look at this and see how they can avoid this yearly debacle that is the Eurovision Song Contest.

“We've only got one neighbour - that's Ireland - and they always give us a vote, but apart from that I can't see where our votes are going to come from. I can only suggest the best way around this would be to avoid the voting of the semi-finalists - that's 18 countries voting who have already been knocked out of the competition. Why are they voting?”

He predicted before the contest that Russia would win. “I think in general the former countries of the USSR are feeling a little nervous, so that's why you had Estonia and Latvia and the other countries all giving 12 points to Russia. I didn't think it was necessarily the best song but I did think it was going to win, and it did.”

Bruce Forsyth and Simon Cowell also said that the system was a farce. Forsyth, who said he did not envy Sir Terry's role as commentator, said: “I agree with him. It's not a song contest any more, it's political. It's all so biased, it's developed into a farce. I've stopped watching it.”

Cowell described the competitive element of the show as meaningless.

Dima Bilan, of Russia, was victorious with 272 points for Believe.

Sir Terry said that Abraham, second on the X Factor television talent contest in 2005, deserved more votes. “It's a disappointment, considering that Andy Abraham gave the performance of his life with a song that certainly deserved more marks than it got.”

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