Spencer Pratt says Kim Kardashian is the ''world's most famous porn star''.

The former 'Hills' star - who is married to Heidi Montag - claims the only reason Kim is famous is because a sex tape of her with former boyfriend Ray J leaked in 2007.

Spencer Pratt was ''very anti-marriage'' before he met Heidi Montag.

The reality TV stars started dating in 2006, marrying two years later, and 29-year-old Spencer admits meeting someone as ''pure hearted'' as Heidi, 26, was a huge shock because of his previous experiences with ''awful women''.

Spencer Pratt and Heidi Montag want to move to Britain and start a family.

The couple - collectively known as 'Speidi' - have fallen in love with the UK since flying over to appear on reality TV show 'Celebrity Big Brother' and have hinted they may settle down and start a family in the British countryside.

Heidi Montag and Spencer Pratt have two former US Marines as bodyguards.

The couple hired the men - nicknamed Venom and Vader - to protect them because of the abuse and threats they received from crazed fans after starring on reality TV show 'The Hills' and the pair keep the marines with them 24/7 to feel safe.

Heidi Montag and Spencer Pratt turned down ''a couple of million'' to star in a pornographic film.

Spencer admits he ''considered'' the X-rated pay day, but his wife - who he previously starred alongside on MTV show 'The Hills' - rejected the offer without hesitation, insisting ''money isn't everything''.