 Nipsa has been involved in strike action since December |
Planning staff in County Antrim are set to join in the long-running civil service pay dispute.
Members of the public service union, Nipsa, working in the Ballymena Borough Council area, are to take industrial action from Monday.
Last week, the government offered Nipsa what it called a "take it or leave it" pay deal in an attempt to end the 38-week long dispute.
Finance Minister Ian Pearson warned that the revised pay deal could not be increased.
However, Nipsa said it would have to consult its members before any offer could be accepted.
 | Areas affected by strike Department of Agriculture and Rural Development Farmers Grants and Subsidies Branch, Londonderry Information Technology Staff, Belfast DoE Planning Service Belfast Area Metropolitan staff, Belfast Administration staff, County Hall, Omagh Strabane District Council planning staff Antrim District Council planning staff |
It is embarking on a three-week consultation period but said its civil service executive committee would be urging members not to accept the pay offer and to vote for all-out indefinite strike action.
Nispa has said that strike action affecting the DoE Planning Service and Department of Agriculture and Rural Development will continue during the consultation period.
Nipsa General Secretary John Corey said: "Our executive committee is firmly of the view that these offers, which are subject to the unfair Treasury limits, are not acceptable and do not resolve this dispute.
Cost of living
"Nipsa is a democratic union and members will now decide in the next three weeks whether or not to accept the pay offers.
"We will be urging against acceptance and we will also be urging members to support all out strike action if we are to carry on with the dispute."
Selective strike action is continuing to hit the province's planning services and grant payments to farmers.
Earlier this month, industrial action was suspended at 15 Northern Ireland MoT centres where workers were on strike since mid May.
Nipsa has been involved in strike action since December over what they said was the government's refusal to give civil service staff any cost of living increases in rates of pay since April last year.
The government has imposed a pay package which will add 3.67% to the wage bill of the Northern Ireland Civil Service.
However, union officials say that was part of a pre-agreed increment and takes no account of the rise in the cost of living.