The winter transfer window is about halfway through and some clubs have been busy trying to strengthen their squad for the business end of the season.

Here are the up-to-date transfers for all clubs who have been active so far in the English Premier League.

ArsenalOut: Harvard Nordtveit (to Borussia Monchengladbach (GER) for £800,000)

Aston VillaIn:Kyle Walker (from Tottenham on loan) Out:Steve Sidwell (to Fulham for undisclosed)

Birmingham CityIn: David Bentley (from Tottenham on loan) Out: Garry O'Connor (to Barnsley for free)

FulhamIn:Steve Sidwell (from Aston Villa for undisclosed)

Manchester CityIn:Edin Dzeko (from VfL Wolfsburg (GER) for £27m)

Manchester UnitedIn:Anders Lindegaard (from Aalesunds (DEN) for £3.5m) Out:Federico Macheda (to Sampdoria (ITA) on loan)

Newcastle UnitedIn:Hatem Ben Arfa (from Marseille (FRA) for £6m) Out: Tamas Kadar (to Huddersfield Town on loan)

Stoke CityIn:Jermaine Pennant (from Real Zaragoza (ESP) for £2.8m)

SunderlandOut:Matt Kilgallon (from Doncaster on loan)

Tottenham HotspurIn:Bongani Khumalo (from SuperSport United (RSA) £1.5m) Out: David Bentley (to Birmingham City on loan) Kyle Walker (to Aston Villa on loan)

Wigan AthleticIn: Adrian Lopez (free agent)