The 35-year-old, who had been on loan with League One side Carlisle United for two months, agreed to end his contract with the Black Cats after two-and-a-half years on Wearside.

Kavanagh has thanked the club and the fans for their support during his time on Wearside.

"I'm gutted that, due to my knee injury, I didn't get to play more games for the club," said the former Republic of Ireland international, who was one of Roy Keane's first signings, joining from Wigan Athletic in August 2006.

"I'll be moving on to pastures new but I'd like to thank everyone at the club, especially the fans for their fantastic support during my time here."

Kavanagh played 15 times for Sunderland, scoring one goal at Leeds United in a 3-0 win at Elland Road, and had two loan spells with Sheffield Wednesday last season, playing 24 matches for the Owls.

The Dubliner joined Carlisle on loan in October, scoring four goals in 17 league and cup matches, and has helped to guide the Cumbrians away from the League One relegation zone.

Kavanagh signed a three-year deal at Sunderland when he joined from Wigan after just over a season with the Latics. He has also played for Cardiff City, Stoke City, Darlington and Middlesbrough during a 17-year career in the game so far.

Meanwhile, Roy O'Donovan has joined Championship side Blackpool on loan until the end of the season.

The 23-year-old forward was recalled from his season-long loan with Dundee United on Monday this week after playing 13 matches for them, scoring one goal.

O'Donovan, who signed for Sunderland from Cork City in August 2007 and made 17 Barclays Premier League appearances last season, has now joined ex-Sunderland defender and fellow Irishman Ian Harte at Blackpool until May.