TDs will today be told exactly what role the current boss of Irish Water had in the troubled Poolbeg incinerator project.

Dublin city manager Owen Keegan will appear before the Oireachtas' Environment committee to discuss spending on the project, which may now be abandoned.

Mr Keegan is expected to be pressed on the role played by his predecessor, who is now responsible for the rollout of water charges.

Our political correspondent Gavan Reilly reports.