The actors, who worked together on That '70s Show, have allegedly been spotted together several times recently and are claimed to have spent the night at each others' houses.
A photographer was quoted by X17 as saying: "Ashton was touching Mila's hand and Mila was all dressed up. She looked hot - this was definitely more than a dinner between friends. This was a full-on date."
The pair have recently been filming a one-off reunion episode for That '70s Show together - which co-star Wilmer Valderrama confirmed by tweeting this picture - although a friend of Mila's insisted to Us Weekly that the pair a definitely just good friends.
But they have apparently been spotted shopping for furniture together before heading out for sushi.
Meanwhile Ashton's estranged wife Demi Moore has returned to social networking site Twitter following her recent stay in rehab.
She sent an upside down self portrait with the word "Testing..."
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