Maria Shriver is ''disgusted'' by Miley Cyrus' nude photo shoot.

The mother of Miley's boyfriend, Patrick Schwarzenegger, is reportedly shocked by the 'We Can't Stop' hitmaker's latest antics, which saw her strip off for V magazine.

A source shared: ''Maria is disgusted by the pictures. She just doesn't get it: why Miley would do this and what the appeal is for Patrick.''

The 59-year-old journalist is not the most supportive of her son's new relationship but is feeling the pressure from her husband, Arnold Schwarzenegger, 67.

The source added: ''She's in a very hard place, she's getting pushed into a corner by Arnold, she doesn't want to be the bad cop.

''The only one still on her side is Katherine [her daughter] and Patrick's wearing her down too.''

Despite his mother's protests, Patrick is believed to be sticking by his girlfriend.

An insider added to HollywoodLife.com: ''He knows what he signed up for dating Miley. She wouldn't like him if he didn't accept her for who she is and he is totally OK with what she does to express herself.

''He is with her on everything she does, as long as she doesn't get hurt he is totally down with everything.''