Johnny Depp and Amber Heard haven't had the smoothest of times but it appears that the actor has finally taken the plunge and popped the question.

According to reports the stars, who met on the set of The Rum Diary, are to be wed.

Depp and Heard have had an on-off relationship.

An insider told The National Enquirer: "He proposed on her birthday. They're not announcing it until the end of the year, but she and Johnny are now on the hunt for a vintage one-of-a-kind ring."

But it doesn't really come as much of a surprise considering Depp recently revealed he wanted to settle down with the 27-year-old actress.

The couple met on the set of The Rum Diary.

Although it apparently took an ultimatum and a fling (Heard briefly dated French model Marie de Villepin during one of her and Depp's breaks) to make him get down on one knee.

The source revealed: "That was exactly what Amber wanted - for the world to know they're together and for Johnny to put a ring on it. She's had a crush on him since she was a teenager, so this is a dream come true!"

If it is true, it will be Depp's first trip down the aisle. Him and his ex-partner Vanessa Paradis never married but do have two children together.