The 24-year-old was named Player of the Season at Kenilworth Road at the end of the 2006-07 campaign and has been in fine form for the Hatters again this term, making 40 appearances and scoring five goals. He has been capped by the Republic of Ireland at both Under-19 and Under-21 level.

A backlog of paperwork at the Football League meant the deal was not ratified until Friday morning, and Bell will go straight into the squad for Saturday's clash against Scunthorpe.

City boss Ian Holloway said: "He's a young, exciting player with a big future ahead of him.

"He can play on either wing as well as in the middle of the park. He will add some much-needed width to our squad. Luton have turned down a number of bids from other clubs for him and we are delighted to have him on board."