Moore sparked speculation on the state of their marriage when she wrote a series of cryptic messages on Twitter.
Kutcher then seemingly addressed the breakup reports by posting a link to the Public Enemy song 'Don't Believe the Hype' on Spotify.
The Two and a Half Men star later insisted that his fans shouldn't "assume" anything about his and Moore's marriage.
Last Thursday, photographs were published of a meeting between Kutcher and a woman bearing "remarkable resemblance" to Sara Leal, who is apparently asking for a $250,000 (£160,000) settlement to keep details of their alleged relationship a secret.
Moore and Kutcher reunited on Friday night for a prayer service at LA's Kabbalah Centre, with both stars wearing their wedding rings, according to X17 Online.
A photographer for the website described the couple's mood as tense, saying: "[Moore] clearly did not want to be photographed… Ashton really looked worried. He wasn't really in a good mood - his MO (modus operandi) was definitely to get into the centre and get out without being seen."
Kutcher and Moore were married in 2005 by a Kabbalah rabbi after dating for more than two years.
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