Manchester City would be interested in signing Raheem Sterling if he were to become available, according to Sky sources.
Tottenham have completed a deal for Cologne defender Kevin Wimmer and he will join them in June, Sky sources understand.
The 32-year-old centre-back, who can number Chelsea, Stuttgart and Sporting Lisbon among his former clubs, has signed a one-year contract at De Kuip after leaving Brondby.
A statement published on Feyenoord's official website revealed Boulahrouz's deal in Rotterdam includes the option of a further year.
He left RKC Waalwijk for Hamburg in 2004 and made 35 appearances for Holland across eight years.