Arsenal are closing in on deals that would see Bolton defender Gary Cahill and Lille forward Gervinho move to the Emirates Stadium.
But Gael Clichy and Cesc Fabregas could be set to leave north London, with Clichy the subject of a £7 million bid from Manchester City.
Fabregas is likely to return to hometown club Barcelona in a £35 million deal, but Arsene Wenger is confident of holding on to Samir Nasri.
Chelsea manager Andre Villas-Boas outlined his plans for the club in his first press conference since taking charge at Stamford Bridge.
Villas-Boas insisted he was ready for the challenges of the Barclays Premier League, emphasising the focus should not be on him, but the team.
The Portuguese also dismissed transfer speculation surrounding Didier Drogba and Michael Essien, insisting they were staying with the club.
Manchester United have completed the signing of 20-year-old goalkeeper David De Gea from Atletico Madrid for around £18 million.
The Spain under-21 international is the latest player to move to United this summer, joining Phil Jones and Ashley Young at Old Trafford.
Liverpool are closing in on deals for Aston Villa's Stewart Downing and Blackpool's Charlie Adam, with the clubs negotiating fees.
Tottenham have been linked with moves for Athletic Bilbao striker Fernando Llorente and £35 million-rated Villarreal star Giuseppe Rossi.
Roberto Mancini is keen to offload fringe players as he looks to add to his squad. M'Baye Niang and Samir Nasri are said to be targets.