  We prove, following Deligne and Andr\'e, that the Hodge classes on abelian
varieties of CM-type can be expressed in terms of divisor classes and split
Weil classes, and we describe some consequences. In particular, we show that
Grothendieck's standard conjecture of Lefschetz type implies the Hodge
conjecture for abelian varieties (Abdulali, Andr\'e, ...).
