Sienna Miller has ordered fiance Rhys Ifans to get into shape.

The 26-year-old ¡®Alfie¡¯ actress ¡ª who has previously dated Hollywood hunks Jude Law and James Bond star Daniel Craig ¡ª has bought Welsh Rhys, 39, a Power Plate and started him on an exercise regime, in the hope of beefing him up before their wedding this summer.

A source said: ¡°Poor old Rhys must find it hard to measure up to her exes. He¡¯s always been quite skinny.

¡°Sienna loves him but she just wants him to tone up a bit so he looks great for their big day.¡±

Last week, Sienna ordered a $7,000 Power Plate exercise machine for the actor so that he can work out at their home in Notting Hill. The trendy ¡°my5¡å acceleration machine uses vibrations to help tone up muscles and increase fitness.

The source added to Britain¡¯s Daily Mirror newspaper: ¡°Rhys received the Power Plate a couple of days ago and he¡¯s been using it already. He¡¯s determined to do whatever he can to make Sienna happy.¡±

Sienna is also forcing the ¡®Human Nature¡¯ star to walk her dogs Porgy and Bess at every opportunity.

¡°Sienna is filming in LA at the moment and she¡¯s left Rhys home alone with instructions to get some exercise. She has been in training for the movie GI Joe, so she thinks they should both be keeping fit,¡± adds the source.

Rhys proposed to Sienna on her 26th birthday with a self-penned poem called Marry This Misfit. They are now planning a starstudded do later this year.

The source adds: ¡°Everything is hush-hush at the moment and they haven¡¯t officially announced their engagement, but Sienna and Rhys are definitely making plans.¡±