We analyse the positions of RR Lyrae stars in the central region of the Milky Way. In addition to the overall bar shape detected previously, we find evidence for a peanut shaped structure, in form of overdensities near $ellsimpm 1^{mathrm{circ}}$ at $bsim-3^{mathrm{circ}}$. The corresponding physical distance between the two peaks of the peanut is $sim0.7,$kpc, significantly shorter than that found from near-IR images (3.3 kpc) and red-clump stars. Qualitatively this is expected from `fractionation of bar orbits, which we demonstrate to be matched in a simulation of an inside-out growing disc subsequently forming a bar.
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