Jade, Mark and The Twins are battling it out for the UK's Eurovision ticket
Andrew Lloyd Webber has said he is worried that one of his Eurovision finalists may not cope well with representing the UK in Moscow.
The composer said that if the public voted for the wrong act he "might not go" to Russia in May, adding: "I really can't be a miracle worker."
He said he would have to "spend quite a lot more time" with one of the acts.
Three acts - The Twins, Jade and Mark - will each perform his Eurovision song My Time on BBC One's live show.
'Rocky power ballad'
"I absolutely know that it would be a mistake to put through somebody who didn't appear to do the song justice," he said, but insisted he would ultimately support whichever act won the public's backing.
He said he did not have a favourite act of the three, but added: "I think I might say there are two.
"If I haven't got the right act there's nothing I can really do to change it," added the musician.
Webber said the song is "a rocky power ballad", with lyrics penned by Grammy-winning US songwriter Diane Warren.
He said the UK would do very well to secure its first top 10 Eurovision finish since 2002, and this was the initial stage in the country's musical comeback.
"I think that's realistically what we can achieve. But, again, we won't achieve it with the wrong act."
But he said the finalists in Your Country Needs You "are infinitely better than anything that Britain has remotely conceived of putting near the stage" in recent years.
Identical siblings Nicola and Francine, Welshman Mark and Londoner Jade will also sing two cover versions during the final show.
The winner, who will represent the UK in the Eurovision Song Contest final on 16 May, is also expected to go on a European tour to promote the song ahead of the competition.
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