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We present a new scheme for the classification of the in-situ and accretedglobular clusters (GCs). The scheme uses total energy $E$ and $z$-component ofthe orbital angular momentum and is calibrated using [Al/Fe] abundance ratio.We demonstrate that such classification results in the GC populations withdistinct spatial, kinematic, and chemical abundance distributions. The in-situGCs are distributed within the central 10 kpc of the Galaxy in a flattenedconfiguration aligned with the MW disc, while the accreted GCs have a widedistribution of distances and a spatial distribution close to spherical.In-situ and accreted GCs have different $\rm [Fe/H]$ distributions with thewell-known bimodality present only in the metallicity distribution of thein-situ GCs. Furthermore, the accreted and in-situ GCs are well separated inthe plane of $\rm [Al/Fe]-[Mg/Fe]$ abundance ratios and follow distinctsequences in the age--$\rm [Fe/H]$ plane. The in-situ GCs in our classificationshow a clear disc spin-up signature -- the increase of median $V_\phi$ atmetallicities $\rm [Fe/H]\approx -1.3\div -1$ similar to the spin-up in thein-situ field stars. This signature signals the MW's disc formation, whichoccurred $\approx 11.7-12.7$ Gyrs ago (or at $z\approx 3.1-5.3$) according toGC ages. In-situ GCs with metallicities of $\rm [Fe/H]\gtrsim -1.3$ were thusborn in the Milky Way disc, while lower metallicity in-situ GCs were bornduring early, turbulent, pre-disc stages of the evolution of the Galaxy and arepart of its Aurora stellar component.

In-situ vs accreted Milky Way globular clusters: a new classification method and implications for cluster formation