Mila Kunis and Ashton Kutcher are reportedly engaged.

The 30-year-old actress has sparked rumours her boyfriend of nearly two years has proposed after she was spotted wearing a diamond sparkler on her ring finger while out shopping in Los Angeles, California, on Thursday (27.02.14).

A source confirmed the news to Us Weekly, adding: ''She is crazy about him!''

The 'Ted' star also uploaded an adorable photograph of her and Ashton - who first met 16 years ago on the set of 'That 70's Show' - on Instagram the day before, which saw them grinning ear-to-ear, accompanied with the caption: ''I love you @kutcher78 (sic).''

The pair first sparked rumours they had got engaged in Decemebr when Mila wore a gold band on her wedding finger ahead of her brother's Michael's wedding.

However, it appears the speculation may be true this time as Ashton's divorced from Demi Moore - whom he separated from in 2011 - was officially finalised in November.

The 36-year-old funnyman started dating Mila, 30, in April 2012 and they have been inseparable ever since.

However, Mila has previously claimed she isn't interested in tying the knot, but hasn't ruled it out in the future.

She said: ''I would love to find 'The One'. But I'm not sure about marriage. I see no need. I'll be with somebody because I want to, not because a piece of paper tells me I have to. That said, if the love of my life thinks it's important, then fine, I'll get married.''