Sneijder, who hasn’t played since September after a contract dispute with his former club Internazionale, finally sealed a €10m (£8.4m) switch to the Türk Telekom Arena after taking over a week to mull over his future.
And the former Real Madrid star revealed that he spoke to both Mourinho and Van Gaal about moving to the Turkish Süper Lig – and both backed the switch.
“I’ve been very well briefed on all sides, very well briefed,” Sneijder told De Telegraaf.
“They both said the same thing: go!
“They gave me the final push, knowing how Turkish football is on the rise.”
And the Netherlands international says a key factor in his decision to join Galatasaray was to ensure that he is in peak shape for next year’s World Cup in Brazil.
“This is all important in view of the World Cup,” he added.
888Sport are offering new customers 21/2 on West Ham to beat Liverpool and Valencia to score any time on your first bet. T&Cs apply. Click here to sign up now.
MORE: The latest football news