Birmingham City midfielder Sebastian Larsson has formally completed his move to Sunderland after signing a three-year deal.

The Black Cats confirmed last week that the 26-year-old Sweden international would be playing his football on Wearside next season, but his move could not officially go through until today following the expiry of his contract at St Andrew's.
Larsson joins Ahmed Elmohamady, Connor Wickham, Craig Gardner and Ji -Dong-Won at the Stadium of Light, with manager Steve Bruce having made significant early progress in his rebuilding plan.
Seb was a fantastic young player for me at Birmingham and he has matured into a very good midfielder.
Steve Bruce on new signing Sebastian Larsson
Bruce signed the former Arsenal trainee for the Blues for £1million in January 2007 after a successful loan spell, and he went on to make 170 appearances. However, he did not agree a new contract with last season's Carling Cup winners.
The manager said: "Seb was a fantastic young player for me at Birmingham and he has matured into a very good midfielder.
"He has been courted by a number of top clubs over the summer - both in England and across Europe - so we are naturally delighted that he has chosen to come to Sunderland."
Larsson and his new team-mates are due to report for pre-season training next week with the club pursuing further targets as they attempt to build on last season's top-ten finish in the Premier League.
Deal for Westwood completed too
The club also confirmed that Republic of Ireland goalkeeper Keiren Westwood has signed a three-year deal.
The 26-year-old agreed a Bosman free transfer to the Stadium of Light last week, but the move could not be finalised until his contract at Coventry City expired at midnight.
Bruce said: "Keiren has proven to be an exceptional goalkeeper both in the Championship and at international level and he has certainly been one of the best in this country outside of the Premier League in recent seasons.
"We are obviously delighted that Keiren sees his future here at Sunderland, and we are looking forward to him joining what is a talented group of goalkeepers at the club."
Westwood began his career at Manchester City, but established himself as a first-team player at Carlisle United, where he made more than 130 league appearances before winning a £500,000 move to Coventry in June 2008.
He has seven full international caps and excelled for Giovanni Trapattoni's men when deputising for the injured Shay Given last season.