Chiwetel Ejiofor has split from his girlfriend Sari Mercer.

The '12 Years A Slave' actor and the Canadian model have reportedly called time on their relationship which came to a ''natural end''.

A source told The Sun on Sunday newspaper: ''It's sad but the relationship came to a natural end.

''Sari was always such a big part of his life so it was definitely a big surprise to hear they had separated.''

Chiwetel, 38, and Sari had been dating for the past few years and split their time between Britain and Los Angeles.

However, the paper reports that he is not sitting around feeling sorry for himself and was spotted flirting with his ex girlfriend, Bond beauty Naomie Harris at the GQ Men of the Year Awards in London last week.

The pair dated eight years ago and are still close with onlookers revealing they appeared in high spirits as they enjoyed a catch up at the event.

Chiwetel has seen his profile rise considerably since starring in Oscar nominated '12 Years a Slave', and previously admitted he is confused by his own fame.

He explained: ''I don't know what all of these things mean yet. In terms of stratification, fame, renown, all these things, it's like an ongoing process of trying to work out what it means.

''Obviously, I'm aware that people react slightly differently to me. It's not like people were rude before, and suddenly they're polite. But yeah, you notice a slight shift, that people are slightly more aware of you - in the street, or whatever.''