Civil and public service workers are stepping up their campaigns against pay cuts.
Health Service Executive workers plan to switch industrial action this week to each region of the organisation.
IMPACT, the country's largest public sector union, is intensifying the first phase of industrial action as part of its ongoing campaign against pay cuts and threats to members' pensions.
HSE workers in the Dublin and northeast region stopped answering telephones from 9am until 1pm.
This action will move to a different HSE region each day - HSE west tomorrow, HSE south on Thursday and the HSE Dublin and mid-Leinster region on Friday.
However, the union has said that Emergency Department telephones and the main switchboards in acute hospitals will continue to be answered.
IMPACT has given notice of its plans to the HSE this week, but said it may not necessarily do so next week.
In another development, members of the Civil and Public Services Union are also intensifying their action over pay cuts.
Members of the CPSU, which represents 13,000 lower paid workers, last night voted in favour of strike action.
Elsewhere, ,the Irish Nurses and Midwives Organisation (INMO) is to ask the public services committee of ICTU to back an escalation of the public sector campaign over pay cuts which would include the withdrawal of labour for short periods.
The proposal will be discussed at a meeting of the committee next Monday, 8 March.
The executive council of the INMO said today that the action should be uniform across the public service and should start as soon as possible.
