In a statement posted on his Twitter account, Kavanagh said: “I’ve taken the very difficult decision to step down as Urlabhraí na Gaeilge & Gnóthaí Gaeltachta and resign from the Green Party/Comhaontas Glas with immediate effect.
“I have never made my opposition to the Programme for Government a secret, having spoken against it at the Special Convention last year.
“Unfortunately, my voicing opposition to Government decisions within the party has been met with a culture I cannot reconcile with the values of the Green Party/Comhaontas Glas.
“I remain committed to serving the people of Clondalkin, Newcastle, Saggart, Rathcoole and Brittas on South Dublin County Council with the support of my former party colleagues.”
Kavanagh was the Green Party Irish language party spokesperson and was involved in Government formation talks last year.