For a list of confirmed transfers, check out the transfers page.
Chelsea will re-sign Serbia midfielder Nemanja Matic, 25, from Benfica for £22m - three years after selling him to the Portuguese giants for £3m.
Sporting Lisbon have entered the race for Manchester United winger Nani, 27.
But Fulham are ready to hijack the deal with their own move for the Portugal international.
Manchester City want to sign Barcelona central midfielder Xavi, 33, to play for their new Major League Soccer franchise New York City FC in 2015.
Manchester United boss David Moyes has held talks with Juventus over a planned double move for 20-year-old Paul Pogba - who left Old Trafford 18 months ago - and fellow midfielder Arturo Vidal, 26.
But Moyes is set to miss out on Benfica's Argentine defender Ezequiel Garay, 27, who is poised for a move to Russian club Zenit St Petersburg instead.
Crystal Palace and QPR may make a move for Carlton Cole, 30, after the former England striker's short-term deal with West Ham expired on Monday.
Everton are interested in signing Kenwyne Jones, 29, from Stoke City. Jones has just six months left on his current deal and Stoke might be prepared to sell the Trinidad and Tobago striker for £1m.
Liverpool defender Tiago Ilori, 20, is in talks over a loan move to La Liga side Granada. The centre-back has yet to feature for Brendan Rodgers's side following his £7m move from Sporting Lisbon in the summer.
Aston Villa boss Paul Lambert will make Wigan striker Grant Holt, 32, his first signing of the transfer window.
Fulham's Costa Rica international forward Bryan Ruiz, 28, is set to join PSV Eindhoven following talks last weekend.
Burnley's 21-goal top scorer Danny Ings, 21, is staying at Turf Moor at least until the end of the season as they bid for promotion to the Premier League, says manager Sean Dyche.
Borussia Monchengladbach's Netherlands international striker Luuk de Jong, 23, says that he is open to joining Newcastle.
Manchester United manager David Moyes will offer captain Nemanja Vidic, 32, a new 12-month deal in a bid to keep him at Old Trafford beyond this summer.
Chelsea boss Jose Mourinho says he wants to stay at Stamford Bridge for the rest of his career.
Andre Villas-Boas is taking a break from the game after losing his job as Tottenham manager last month.
Real Madrid coach Carlo Ancelotti has admitted that selling Germany midfielder Mesut Ozil, 25, to Arsenal in September was a mistake.
Winger Raheem Sterling, 19, has what it takes to win a place in England's World Cup squad, according to his Liverpool team-mate and national team captain Steven Gerrard.
Paul Ince insists he will not quit as Blackpool manager despite a run of seven defeats in eight Championship games.
Stoke keeper Jack Butland, 20, has posted an appeal on Twitter for help to track down his car - which was stolen hours before he made his full Premier League debut in Sunday's 5-3 defeat at home to Liverpool.
Tottenham striker Jermain Defoe, 31, admits that his move to Major League Soccer side Toronto might damage his hopes of earning a place in England's World Cup squad.
Chelsea midfielder Frank Lampard, 35, is likely to be fit to face champions Manchester United at Stamford Bridge on Sunday following a positive scan on his thigh injury.
Bacary Sagna, 30, is set to hold fresh talks with Arsenal about a new contract. The France defender's current deal with the Gunners expires at the end of the season.
Former Manchester United manager Sir Alex Ferguson has enjoyed a happy atmosphere during a sunshine break in Barbados - after being joined by comedian Russ Abbot.
Ex-England keeper Paul Robinson's match-winning display for Blackburn against Doncaster on Saturday has won the 34-year-old a famous fan - One Direction singer Louis Tomlinson, who watched from the stands at Ewood Park.
QPR midfielder Joey Barton, 31, caused a storm on Twitter by cheekily suggesting he was a certainty to win the Ballon d'Or.
Have your say on these stories on the BBC Sport Facebook page.