Mila Kunis and Ashton Kutcher have fuelled speculation suggesting the former TV co-stars are dating after sharing a kiss at a Los Angeles party.

The couple was photographed smooching during an afternoon bash on Saturday.

An eyewitness to their public display of affection tells UsMagazine.com, "They were seated on a couch on the same side of the table and Mila was running her hands through Ashton's hair. She had her elbow resting on his back and couldn't stop playing with his hair and rubbing his shoulders."

Neither Kunis nor Kutcher have commented on the ongoing dating reports.