The former Rangers, Sheffield Wednesday, Dunfermline Athletic and Sligo Rovers player joins the Glebe Park team ahead of Saturday's home match with Elgin City.
Manager Mark Wilson told the club website: “We're delighted to have someone of his calibre on board to help us in our fight to avoid relegation. Rhys fitted all the criteria we were looking for - an experienced player and a great leader and talker - as well as being a good footballer.”