Sienna Miller Liplocks With Boyfriend During Airplane Ride

Sienna Miller and Rhys Ifans left fellow passengers amazed as they openly frolicked during their 12-hour flight home from the Oscars.

The stunning actress and the 'Notting Hill' star - who began dating last year - couldn't keep their hands off each other from the moment they boarded a London-bound plane in Los Angeles.

An onlooker told Britain's Daily Mirror newspaper: "They were cavorting for almost the entire flight. They kissed each other passionately, before stroking each other's hair, nibbling, whispering and giggling with each other."

During the flight, Rhys even stripped off his shirt after spilling wine all over it. Fellow passengers claim their passion - part of which took place in Sienna's fully-reclined seat - was only interrupted when a flight attendant served them dinner.

Sources say the pair are so smitten with each other that Rhys is planning to propose.

The 39-year-old star is said to have hidden a number of marriage proposals in several boxes of Sienna's favorite perfume, which she is taking to Los Angeles where she is filming her new movie 'GI Joe' next month.

A source revealed: "He stuck a marriage proposal at the bottom of each bottle using a secret system of letters and numbers, because her new film involves her decipher codes. He loves his ingenious plan and hopes she cracks the code and he gets the answer he wants!"