The additive electrochemical nano-fabrication with scanning probes beyond cluster size has been proven to be difficult, opposite to what could be expected from conventional electrochemistry. The main reason being that when the tip/substrate gap is of the order of nanometers, the reaction dynamics are governed by a complex interplay of electrochemical potential distributions, poor communication with the bulk solution and mass transport limitations of ions into the small gap. In general, effects of the structure and dynamics of the electrical double layer (EDL) at the solid-liquid interface on nanoscale electrochemistry are not fully understood . In the past years, several groups have focused on using scanning probe microscopy techniques to probe the solid-liquid interface , in terms of specific adsorption , charge density , and screening . In all these works, care was taken to ensure minimal perturbation of the EDL by the probing tip. However, it has been suggested that in some cases, the probe may strongly perturb the charge distribution at the interface. Schuster and co-workers demonstrated the etching and deposition of metals with micrometer resolution by locally polarizing the EDL at the water-substrate interface upon the application of a voltage pulse at a microelectrode . The authors described the reaction confinement by considering a simple RC equivalent circuit, concluding that nanometer resolution would require fs pulses. However, this timescale is much faster than the typical electric double layer dynamics (˜ns -µs). Interestingly, nanoscale local etching and depostition has been demonstrated with µspulses to an STM tip. In this work, we take advantage of the capabilities of an electrochemical atomic force microscope (EC-AFM) tip to dynamically perturb the EDL in order to control growth at the nanoscale. We achieve this by using a highly dilute electrolyte and highly asymmetric tip-substrate system (in terms of material and potential). We demonstrate direct electrodeposition of copper on gold, with lateral dimensions down to tens of nanometers and aspect ratio above 0.5. We show a critical dependence of the ability to confine growth on the salt concentration, as well as the dynamics of the tip movement during the writing. We propose a local growth mechanism facilitated by a combination of periodic disruption and build-up of the EDL, followed by forced electrodeposition due to the strong perturbation of the electrochemical potential between the tip and the sample.