Prince Harry's relationship with girlfriend Cressida Bonas is reportedly 'on the rocks' as she does not want to get married so soon.

According to the Sunday People, the 24-year-old socialite wants an acting career and ''hates the idea of being a trophy wife.''

"The relationship is not firing on all cylinders," a friend said, "One minute it is terrific and the next ­moment they are breaking up. It's not as hunky-dory as it was."

"Harry wants to get married and settle down. He is ready to calm his life down and wants to do that with Cressida. Sadly for Harry, she thinks she is too young to do that. She likes to go out and enjoy herself and is a long, long way off being anyone's wife let alone a royal wife," the source said, adding, "Cressida wants to become an actress and has made it clear she is not interested in being a trophy wife. There are problems with this relationship which are ­irreconcilable. Cressida is very hot and cold and Harry isn't entirely sure what is going on all of the time."

Prince William and Kate Middleton are also said to be unhappy about his choice of girlfriend. Ironically enough, Bonas is the half-sister to Prince William's former girlfriend, actress and model Isabella Anstruther-Gough-Calthorpe.

"Kate can't ­countenance anything with that girl. Kate will not want to be reminded of that unhappy period in her life," another friend said.

Prince Harry and Bonas were spotted together for the first time in February while skiing in Verbier, Switzerland. There were also reports that the 29-year-old royal is set to propose the daughter of 1960s model Lady Mary Gaye Curzon and Old Harrovian businessman Jeffrey Bonas. Bonas was reportedly in flood of tears following marriage talk.

Prince Harry had previously dated Zimbabwean national Chelsy Davy and later, he shared a brief fling with Jenson Button's former girlfriend Florence Brudenell-Bruce.