Plot of the Larson’s relations for the giant molecular clouds (black points). The top row shows the M−R (left) and σ−R (right) relations. The bottom row shows the σ−M (left) and σ−ΣR (right) relations. We also plot the 2D histograms and the best fitting relations (colour scale and black line) for the molecular clouds in the Milky Way (Miville-Deschênes et al. 2017). The molecular clouds in the northern filaments of Centaurus A are consistent with those of the Milky Way. We also indicate the limits on the radius and velocity dispersion that can be reached owing to resolution or filtering effects (18.1 ≤ R ≤ 260pc, σ_v> 1.25km s^-1; horizontal and vertical black lines).