Manchester United manager Louis van Gaal says Argentina midfielder Angel Di Maria's departure to Paris St-Germain is a "big loss".

Di Maria has signed a four-year deal with the French champions for a fee of £44.3m, and leaves United just a year after they paid Real Madrid a British record £59.7m for him.

Van Gaal says the Red Devils "have problems with David De Gea" and says the Spain goalkeeper will not face Tottenham on Saturday.