A source revealed, "Rosie and Jason have had many ups and downs in their relationship, but the supermodel has begun to lay down the law that if Jason doesn't start getting serious about getting married, she will leave him."

However, the insider said, "But the ultimatum idea didn't come from Rosie herself but her close pal and 'mentor Miranda!"

Huntington-Whiteley, has been dating "The Expendables" star, 46, since 2010. She previously dated Tyrone Wood, the son of Rolling Stones member Ronnie Wood for two years and briefly dated actor Olivier Martinez.

Meanwhile, Statham, whose ex-girlfriend was British model, Kelly Brook, has never been married.

However, it seems that, Kerr, 30, thinks it is time for the actor to commit to his girlfriend with a ring. A source explained, "After Rosie and Jason have spent four years together, Miranda would like to see her get married. She only wants the best for her friend, so she's urging her to give Jason some tough love."

Miranda Kerr married Orlando Bloom back in 2010 and the two share a son, Flynn, however, they announced their separation in 2013.

Despite her failed marriage, the model is encouraging Huntington-Whitley to force her boyfriend to get serious.

The insider explained, "Miranda has been bragging to other friends in recent weeks that she is steering Rosie in the right direction by advising her to leave Jason if he doesn't propose before the summer."

Do you think Miranda Kerr should be giving Rosie Huntington-Whiteley advice on her relationship with boyfriend Jason Statham or should she just mind her business? Let us know your thoughts in the comment section below.