Fianna Fail says that the mental health budget is being pick-pocketed by senior Government ministers.
The opposition party says money put aside for mental health services is being used for other areas of the health service.
The party's spokesperson on mental health says there is currently a shortage of over 3,000 mental health workers in the system.
It comes as it's emerged that the HSE is paying €4.4 million a year for patients to receive specialist mental health treatments in the UK.
Deputy Colm Keaveney says mental health services need urgent investment: