Virgil van Dijk claims he knows nothing of interest from English clubs and is keen to prove himself in the Champions League with Celtic.
QPR loanee Tom Carroll wants to "make it at Tottenham" but is prepared to consider all of his options at the end of the season.
Defender Dale Bennett has seen his contract at Watford cancelled by mutual consent.
The Academy graduate, 23, made his Hornets debut in a League Cup encounter against West Ham in September 2008 but has failed to nail down a regular first-team place at Vicarage Road.
Bennett has made a total of 25 appearances for Watford, 16 of which starts.
He also spent time on loan at Kettering, Brentford, AFC Wimbledon and Yeovil - the latter two coming over the first half of this season.