He says they have until Friday to reverse their decision.
It's up to Fianna Fáil to stop the development of a windfarm on Leamonaghan Bog in Offaly.
That's the call from independent councillor Sean O'Brien, who says the party's eight councillors are to blame for voting to have the land in Ballycumber designated for windfarm development.
A record 2,300 objections to the decision were made to the local authority.
Councillor O'Brien says this Friday's meeting of the council is the last chance to change the decision, as Bord na Móna will be going straight to An Bord Pleanála to get permission to build: