(Cover) - EN Showbiz - Ashton Kutcher appeared "awkward" at a charity event he attended alone.

Ashton and his wife Demi Moore are rumoured to be on the brink of divorce following the Two and a Half Men's star alleged highly publicised extramarital affair.

At GQ magazine's Gentlemen's ball in New York City yesterday Ashton appeared uncomfortable.

It seemed as if Ashton was attempting to conceal his wedding ring throughout the function.

"[Ashton looked] awkward," an eyewitness told Life & Style magazine.

"It was weird even when he was shaking someone else's hand or giving a hug, he kept his hand in his pocket. When he did take it out, I saw that he was wearing his wedding ring, but for the most part he kept his hand in his pocket. It was very unnatural."

Ashton visited the event to speak in support of ending human trafficking and the sex-trade industry. He and Demi have been vocal about this issue in the past.

Without his wife in attendance Ashton seemed anxious when greeting other guests.

"[Ashton looked] tense. While he definitely put on a brave face and smiled, it seemed as though he was eager to get the night over with."

Ashton was reported to have had an affair in a California hotel room with 22-year-old Sara Leal during his and Demi's sixth wedding anniversary last month. (C) Cover Media