Celtic have completed the signing of Aston Villa attacker Shaun Maloney on a four-year contract.

The 25-year-old made his Celtic debut in April 2001 but left for Villa Park in January 2007 for a £1million fee after failing to agree new terms with the Scottish champions.

Maloney has returned north for a fee which could rise to £2.5million, according to the Aston Villa website.