A bidding war for Bob the Builder is brewing after his owner confirmed two further approaches aimed at scuppering a planned £489 million takeover.

Hit Entertainment, whose other brands include Thomas the Tank Engine and Pingu, said it had received two " unsolicited early stage approaches" and that other potential buyers had requested information.

One of the advances came from Lions Gate Entertainment, the US media giant behind children's favourites The Incredible Hulk and Inspector Gadget.

A source close to the situation said the Lions Gate offer could be around £534 million, compared with the £489 million deal with Apax.

The company said: "Whilst Hit is investigating these approaches, their preliminary nature means that there can be no assurance that they will lead to a further offer for the company."

Lions Gate has confirmed it had requested access to Hit's books because it was considering making an offer.

Hit confirmed on March 21 that it had agreed to be bought by private equity giant Apax partners.

The proposed deal was backed by Hit's independent directors and had at the time of the announcement secured the support of investors owning 35 per cent of its shares.

Hit said that it planned to send out information on the offer from Apax's bidding vehicle Sunshine Acquisition to shareholders in the next few days.

Half- year results unveiled by Hit at the time of Apax's announcement showed the impact of tougher trading conditions, as underlying profits fell by almost half to £13.3 million.

The company hopes that moves to revitalise the Bob the Builder brand will improve its prospects.

Hit is the fourth biggest children's video distributor in the UK and the United States and the world's fourth biggest children's character licensing company.

Los Angeles-based Lions Gate is the largest independent entertainment company in the US, producing and distributing motion pictures, home entertainment, family entertainment, television programming and videoon-demand products.

Charles Whitworth of brokers Williams de Broe said a rival suitor would have to offer a generous premium to Apax's 300-pence-a-share offer.

Mr Whitworth said: "At the moment my money is still on Apax. For Lions Gate to succeed they would need to have a very clear growth strategy for the US."