Hedge fund manager Crispin Odey has said he is considering withdrawing his support for Twenty-First Century Fox's attempt to take over Sky, saying he believes the 11.7 billion pound ($15.20 billion) deal undervalues the British broadcaster.

Odey, who is the 15th biggest Sky shareholder with a 1 percent stake according to Thomson Reuters data, had said he backed the bid when it was announced in December.

However, he told Reuters that regulatory delays have prompted him to reconsider his support for Fox's 10.75 pound a share offer for the 61 percent of Sky it does not already own.

His change of stance comes after Rupert Murdoch's attempt to take full control of Sky faced another obstacle when the British government's Department for Digital, Culture, Media and Sport said on Tuesday it had asked communications regulator Ofcom to re-examine the deal.

"The truth is, the longer this goes on the more that I would be quite happy if it failed," Odey said, adding that Fox is "getting it at what now looks like quite a cheap price" and that the offer is "now starting to look rather mean."

Odey said in a telephone interview his view of the deal was changing because he thought Sky's prospects were improving.

The investor clashed with the broadcaster three years ago when he initially rejected its offer to acquire his fund's shares in Sky Deutschland as part of its takeover of the German business.

A spokesman at Sky declined to comment.

Sky shares fell on Tuesday following the announcement that Ofcom had been asked to do more analysis on the deal, adding another delay that unnerved investors.

The stock was trading on Wednesday at 955.5 pence, the lowest level since December when news of the deal broke.

A source close to Sky cautioned that at the current share price, Fox's offer remains competitive. However, he acknowledged that the longer the deal takes the higher the risk is that investors may change their views on valuation.

Murdoch has long sought to take full control of Sky but has faced political opposition.

An earlier attempt to take over the broadcaster was abandoned in 2011 amid a furore over a phone-hacking scandal at the now-defunct News of the World, a paper the billionaire had owned.