Spencer Pratt has reportedly decided against releasing sex tapes featuring his estranged wife.

The reality TV star had threatened to release three raunchy films of Heidi Montag - who he separated from in April after a year of marriage- if she refused his pleas to rekindle their romance and make a new television programme, but has now apparently changed his mind as the blonde beauty is refusing to authorise making the footage public.

According to gossip website TMZ, Spencer's assistant wrote to Vivid Entertainment - the adult film company who were in negotiations to release the tapes - and said: "Heidi's made it very clear that she is not interested in releasing any tapes. It looks like she pulled the kill switch.

"Spencer's not interested in further destroying their relationship by pursuing an avenue she's so vehemently against."

According to the letters, Spencer was apparently surprised that Heidi turned down the chance to make a huge sum of money from the videos - two of which also feature her estranged husband while the third depicts her with close pal Karissa Shannon - and has threatened legal action if the footage is made public.

The letter added: "Spencer thought $5 million would be enough to convince her, but now Heidi is saying she'll bring out the legal team if he persists."