The Scotland international, who has previously played for Tottenham and Rangers, is out of favour at Villa Park and has been forced to train away from the first team.
Villa hoped to sell the 27-year-old during the recent transfer window but were unsuccessful and boss Lambert has now stated the defender could leave on a temporary basis.
"There could be a chance of him going out on loan," manager Paul Lambert told the Daily Mirror.
"I've told him that if there is something there then he can look at it. I've always been honest with him. I think that is the best way of being honest with people. He knows the situation."