On gauge invariance and ward identities for the Wilsonian Renormalisation Group

We investigate non-Abelian gauge theories within a Wilsonian Renormalisatio n Group approach. The cut-off term inherent in this approach leads to a mod ified Ward identity (mWI). It is shown that this mWI is compatible with the flow and that the full effective action satisfies the usual Ward identity (WI). The universal 1-loop beta-function is derived within this approach an d the extension to the 2-loop level is briefly outlined.