The invention relates to a process for producing a supported silver catalyst, having the following steps: (a) reacting oxalic acid with an alkali metal base in a solvent, preferably water, up to the second equivalence point of the oxalic acid, thereby obtaining alkali metal oxalate; (b) reacting the alkali metal oxalate obtained according to (a) with a silver salt in a solvent, preferably water, thereby obtaining silver oxalate; (c) complexing the silver oxalate obtained according to (b) with a diamine compound in a solvent, preferably water, thereby obtaining a diamine-silver oxalate complex.