LTE lithium abundances for a set of 20 Gaia-benchmark stars. Left panel: literature abundances compared to the AMBRE/Li determinations. Middle panel: lithium abundances derived from the AMBRE spectra and adopting the literature atmospheric parameters compared to the AMBRE/Li determinations. Right panel: lithium abundances derived from the AMBRE spectra and adopting the Gaia benchmark stars (GBS) atmospheric parameters compared to the AMBRE/Li determinations. Lithium abundances are shown in red, while upper limits are represented by blue arrows. Mean differences and standard deviations for the lithium abundance are reported. Stars and references of the literature values are the following: ϵ Eri, β Vir (Gonzalez et al. 2010); α Cen A, 18 Sco (Baumann et al. 2010); HD 22879 (Nissen & Schuster 2012); Sun (Grevesse et al. 2007); τ Cet (Takeda & Kawanomoto 2005); α Cen B (Chmielewski et al. 1992); μ Ara, δ Eri, β Hyi (Bruntt et al. 2010); Procyon, HD 49933 (Ramírez et al. 2012); HD 84937 (Lind et al. 2013); HD 140283 (Asplund et al. 2006); ϵ For (Lèbre et al. 1999); Arcturus (Reddy & Lambert 2005); ϵ Vir, α Tau (Mallik 1999); and HD 107328 (Brown et al. 1989).