Beyonce Knowles marriage to Jay-Z is a 'power struggle'

Beyonce Knowles says being married to Jay-Z is a "power struggle".

The 27-year-old singer - who wed the music mogul in April - admits the relationship can sometimes be tiring, but she wouldn't have it any other way.

She said: "My marriage is a power struggle. But if I didn't respect someone, and they didn't have that strength, then I would be bored. I wouldn't be attracted to them."

Beyonce also revealed her mother Tina was banned from the set when she filmed upcoming movie 'Cadillac Records', because she wasn't used to seeing her daughter curse.

Beyonce, who plays blues singer Etta James in the film, added to America's Elle magazine: "My mom had to leave the set. I don't normally curse. Maybe twice a year. I have to be really livid. Somebody saying things or scheduling something where I'm not in control.

"Cursing was freeing, but the shoot was also the most emotionally draining time of my life. Every day I would come home - my eyes would be completely swollen."