Let K be a field of formal Laurent series with coefficients in a finite field of characteristic p, G 0 we construct epimorphism of Lie algebrasη † : L −→L † and the action Ω U of the formal group α p = Spec F p [U ], U p = 0, of order p onL † . Suppose dΩ U = B † U , where B † ∈ DiffL † , and L † [v 0 ] is the ideal ofL † generated by the elements of B † (L † ). The main result of the paper states that L (v0) = (η † ) −1L † [v 0 ]. In the last sections we relate this result to the explicit construction of generators of L (v0) obtained earlier by the author and develop its more efficient version.