Crystal Palace co-chairman Steve Parish has confirmed the club are in talks to sign Paris Saint-Germain midfielder Yohan Cabaye.
Tottenham have agreed a deal for Atletico Madrid central defender Toby Alderweireld, according to reports in Italy.
The Dutch left-back has agreed his third spell with the Eredivisie club having also spent time in his homeland in the second half of the 2011/2012 season, along with all of the last campaign.
Van Aanholt, 22, is highly rated at Chelsea, who on Friday signed midfielder Marco van Ginkel from Vitesse, but he would face tough competition for places with Ashley Cole and Ryan Bertrand.
A statement on Vitesse's official website read: "Patrick van Aanholt will play again next season at Vitesse.
"The 22-year-old defender is hired for a season from Chelsea Football Club. Van Aanholt begins his third season in Arnhem."