  We study the equilibrium measure $\mu$ = T $\land$ T of endomorphisms f of
CP(2) of degree d $\ge$ 2, where T is the Green current of f. Dujardin proved
that if $\mu$ is absolutely continuous with respect to T then f has a minimal
Lyapunov exponent [12]. We show the reverse implication under a local uniform
assumption on unstable manifolds of the dynamical system.
