The 27-year-old Blackburn player will go straight into the squad for tomorrow's Championship clash with Plymouth at St James's Park ... but is cup-tied and won't be able to play against Peterborough in the Carling Cup.
Chris Hughton: "Zurab is an experienced defender, and we're very pleased to get him on board. He knows English football very well, and will be a valuable addition to the squad over the coming months."
He ho has 62 senior international caps and began his career with Dinamo Tbilisi.
After spells with city rivals FC Tbilisi and then Lokomotiv Tbilisi, he made his way to Scotland, playing for first Dundee, and then Rangers.
He joined Blackburn in a £500,000 move during the summer of 2006 after spending a successful season on loan at Ewood Park.
He has made just one senior appearance this season, which to Newcastle's regret, was in the Carling Cup.