Buckley joined Sunderland in August 2014 for a fee in the region of £2.5m, and was one of Gus Poyet’s recruits from former club Brighton. The Englishman has made only 24 appearances for the Black Cats, and has failed to get on the scoresheet.
Buckley had a brief loan spell with Birmingham’s Championship rivals Leeds United earlier in the season, where he made four appearances.
Speaking to the media, Blues boss Gary Rowett had this to say about his new signing:
When he played at Brighton, he was perfect for a counterattacking system, He’s very athletic, good pace, two footed, travels well with the ball and has that little bit of Premier League quality in the final third
Birmingham currently sit 9th in the Championship, with 40 points from 26 games. Their next challenge is a trip to Pride Park to face third-placed Derby County.