A version of the perturbation theory is developed for determining the field distribution of spatial solitons with a 2D transverse profile in a medium with saturable absorp- tion and gain in the case of small deviations from paraxial conditions. Starting from the unperturbed paraxial soliton with the linear polarisation of radiation, an approximate maste equation is derived for radiation, an approximate maste equation is derived for transverse components of the electric field in the case of wide solitons. It is shown that its solution represents a stable weakly nonparaxial dis- sipative optical vector soliton with an axially saymmetric field distribution.
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