After being together for five years Naomi Campbell and Vladimir Doronin are reportedly on a break.

Naomi and the Russian billionaire are taking a temporary time out from each other. The couple was last seen together in Miami in March.

"Naomi and Vlad have a complex relationship, and sometimes break up and make up," said a source. "In many ways their relationship is like a business arrangement. Naomi brings glamor to his hotels and properties, and he treats her extremely well. But they spend a lot of time apart due to work commitments."

The supermodel, 42, has had numerous work commitments over the past few months with her modelling competition show The Face proving to be a huge hit. So much so in fact, that a UK version of the show is in production.  Naomi is a tough talking, no holds barred judge of the reality TV modeling competition.  She has a fit if things sdon't go her way and is ruthless to the other judges.  Not surprising that Vladimir needs a break from her.

Vladimir was seen most recently at the Rose Bar at the Gramercy Park Hotel with an unidentified beautiful blonde.

Naomi and Vladimir have been rumored to be engaged several times but have always denied the reports.

Vladimir is still not legally divorced from wife Ekaterina, despite the fact the pair split in 1998. 

Most likely, the billionaire is not ready to give up some of his billions.