G-Pisa is an experiment investigating the possibility to operate a high sensitivity laser gyroscope with area less than $1 rm m^2$ for improving the performances of the mirrors suspensions of the gravitational wave antenna Virgo. The experimental set-up consists in a He-Ne ring laser with a 4 mirrors square cavity. The laser is pumped by an RF discharge where the RF oscillator includes the laser plasma in order to reach a better stability. The contrast of the Sagnac fringes is typically above 50% and a stable regime has been reached with the laser operating both single mode or multimode. The effect of hydrogen contamination on the laser was also checked. A low-frequency sensitivity, below $1 rm Hz$, in the range of $10^{-8} rm {(rad / s)/ sqrt{Hz}}$ has been measured.
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