The superstar couple are said to be in final negotiations with E! - the production company behind Kim's reality show 'Keeping Up With The Kardashians' - who are said to be part-funding Kanye and Kim's big day.
Jay-z and Beyonce are in talks to pick up the staggering sum for playing a ''short show'' during the nuptials.
A source said: ''Jay Z and Beyonce will also perform at the wedding, as long as their last-minute negotiations with E! work out.
''The two have demanded $2 million for a short show.''
Kim, 33, is said to have spent a further $2million on a wedding gown - although she remains undecided on what to wear for her big day.
She even called Alexander McQueen's Sarah Burton - who created the gown Kate Middleton wore to marry Prince William at the Royal Wedding in 2010 - to design another option for her to choose from for the elaborate ceremony.
A source told RadarOnline.com: ''The two have planned a rehearsal dinner that costs an estimated $650,000.
''And they are paying for a lot of that. Chefs from around the world are being flown in to prepare dinner for the rehearsal night and the reception dinner after the wedding.
''High-end and extensive security is costing $3 million, flowers are $1 million and food is about $2,000 a plate.''
The day will be finished off with a $200,000 fireworks display.