Beyonce is reportedly fuming at Jay-Z for having a secret phone to call his protegee Rihanna .
The pop star, who has been married to the rapper for seven years, is said to have been rowing with her husband over the singer after she discovered the mobile which is reportedly for business purposes.
A source told Grazia magazine: "Jay has several phones, one of which he keeps reserved for Rihanna, supposedly to discuss business interests.
"It's obvious when she calls because he'll interrupt meetings, even walk away from the dinner table to speak to her."