A method of making a lithographic printing plate includes the steps of: a) providing a lithographic printing plate precursor including (i) a support having a hydrophilic surface or which is provided with a hydrophilic layer, (ii) a coating on the support including a photopolymerizable layer, and, optionally, an intermediate layer between the photopolymerizable layer and the support, wherein the photopolymerizable layer includes a polymerizable compound and a polymerization initiator, b) image-wise exposing the coating in a plate setter, c) optionally, heating the precursor in a pre-heating unit, d) developing the precursor off-press in a gumming unit by treating the coating of the precursor with a gum solution, thereby removing the non-exposed areas of the photopolymerizable layer from the support, wherein the photopolymerizable layer further includes a polymer containing an acid group and a basic nitrogen-containing compound capable of neutralizing the acid group, or wherein the photopolymerizable layer further includes a polymer containing an acid group which is neutralized by a basic nitrogen-containing compound.