text: "Nobody risks £15,000 on a hunch," said a spokesman for William Hill, who make the band 6/4 favourites to get the gig.
  Ladbrokes, Coral and Paddy Power have also suspended betting.
  A spokesman for Radiohead said he had "no comment" on whether the band would be performing the Spectre title track.
  Bond star Daniel Craig is known to be a Radiohead fan, having quizzed frontman Thom Yorke for Interview magazine in 2013.
  Speculation about whom will sing the song has been feverish in recent days, with Ellie Goulding emerging as another favourite.
  The star posted a photo on Monday that appeared to hint she had been chosen.
  "That's a wrap!" the singer wrote on Instagram, next to a photograph of her leaving Abbey Road studios in London.
  The historic recording facility was where Adele recorded the title track for Skyfall, the previous James Bond film, in 2012.
  The Showbiz 411 website reported on Tuesday that Goulding had registered a song called Spy with music rights organisation BMI, a song it suggested was the theme song for Spectre.
  According to NME, though, a spokesman for the singer later confirmed she had been working on her new studio album at Abbey Road.
  "The first gamble of the day was Ellie Goulding and punters were backing her as if she already had the gig," said William Hill's Rupert Adams on Tuesday.
  "But just as we were thinking of pulling the plug we had a load of bets for Radiohead, including one customer who asked to place a £15,000 bet on the band at 10/1."
  If Yorke's band are chosen to record the title track for Spectre, it would be the first group to sing a James Bond title song this century.
  The last band to have that honour was Garbage, who performed the title track for The World is Not Enough, in 1999.
  The makers of Spectre have yet to announce who will sing the song, though director Sam Mendes has confirmed a song has been recorded.
  "It's fantastic and I'm very excited about it," he told BBC Radio's Test Match Special. "You won't have to wait long."
  Sam Smith, another mooted candidate, denied rumours he would be singing the theme tune earlier this month.
  "People seem to think I'm doing it but I have no idea what's going on," he told Capital FM. "I think I would know by now."
  A spokeswoman for Coral told the BBC the bookmaker had decided to suspend betting on Tuesday following Goulding's cryptic hint.
  A spokesman for Paddy Power said it had not accepted any bets since Mendes' confirmation that an artist had been chosen, while Ladbrokes' spokeswoman said it suspended betting last week.
  "We're no 007, but money talks, and with Ellie proving to be punters' Bond girl of choice we had no option but to suspend betting on her recording Spectre's theme song," said Ladbrokes' Jessica Bridge.
target: A leading bookmaker is refusing to take bets on which artist will record the next James Bond theme song after one customer tried to place a £15,000 wager on Radiohead being selected.