We analyze the asymmetric part of the ring current (RC), which appears during the main phase of a magnetic storm and is due to strong precipitation of RC ions into the ionosphere. The precipitation is caused by the pitch angle scattering by ion cyclotron waves and is localized in the evening sector inside the storm time plasmaspheric bulge. The asymmetric (partial) RC together with the precipitation decreases the electric shielding of the inner magnetosphere by the region 2 current system and forms an additional three-dimensional current system at subauroral latitudes. Using a simplified analytical model, we show that such a current system can be a good candidate for explaining the origin of the polarization jet (subauroral ion drift, PJ/SAID), In particular, spatial-temporal characteristics, ionospheric ion velocities, and electric field values for this current system correspond to those in the PJ.