The former Hearts captain parted company with Leeds by mutual consent yesterday, with the final year of his contract terminated, with the 30-year-old one of several senior players expected to leave United in the coming days and weeks.
The futures of the likes of Paddy Kenny and Stephen Warnock also appeard in doubt.
Lithuanian centre-half Zaliukas almost joined the Gers last summer and trained with the club, only for a deal to break down following his release from Hearts.
After mulling over the offer, he elected not to sign a contract after mulling over the contract, with the stopper linking up with United in the autumn, signing an 18-month deal at Elland Road.
But it looks to be a case of second time lucky for Gers chief Ally McCoist.