The method comprises (a) catalytic cracking (FCC) of a heavy cut producing a cut petrol C5-220[deg] C when the FCC is directed towards the production of petrol and C5-150[deg] C when the FCC is directed towards the production of average distillate, (b) performing selective hydrogenation of the cut petrol output from a catalytic cracking unit (2), (c) separating the petrol output from of the step (b) by distillation to separate two cuts including a cut light petrol C5-pF and a cut heavy petrol pF-220[deg] C, and (d) purifying light petrol C5-pF output to reduce nitrogen to less than 0.2 ppm. The method comprises (a) catalytic cracking (FCC) of a heavy cut producing a cut petrol C5-220[deg] C when the FCC is directed towards the production of petrol and C5-150[deg] C when the FCC is directed towards the production of average distillate, (b) performing selective hydrogenation of the cut petrol output from a catalytic cracking unit (2) functioning at a pressure of 0.5-5 MPa, a temperature of 80-220[deg] C and liq