The Director General of the Workplace Relations Commission has said that the "side deals" connected to the new public service pay agreement are part and parcel of industrial relations.

It emerged last week that thousands of public servants including nurses, midwifes, prison officers, firefighters, radiographers and craft workers will see the restoration of certain allowances if their unions sign up to the new public service pay agreement.

The package of allowances will cost €10 million over and above the €880m cost of the three-year pay deal.

Asked if the WRC was aware of these side deals, Oonagh Buckley said it is commonly the case that the employer and representative bodies sit down and deal with specific issues because they are in the same building together and issues come up all the time.

"They're known as side deals," she said, "but to be honest it’s a fairly regular part of the process and it isn't anything particularly to be concerned about."

In this case, Ms Buckley said the Department of Public Expenditure and Reform was concerned to make sure they were costed and made public fairly quickly so that is why they came out last week.

She said: "It's a very standard part of the process, these sorts of arrangements are done in between pay rounds all the time but it's just simply that people were together dealing with issues as they came up and they all happened to be in Lansdowne House together so it was a very opportune time."

Ms Buckley was speaking as the Government Chief Whip Joe McHugh officially opened the first regional services centre of the WRC in Sligo.

The centre is the first outside of Dublin to provide the full range of WRC services including mediation, conciliation and arbitration.

The services are free and mean that people in the region no longer have to travel to Dublin for face-to-face meetings to resolve issues.

Mr McHugh said the service was important for the protection of workers and employers and 90% of WRC adjudications are accepted.

Ms Buckley said the WRC is just two years old, but its services are very broad and are critically important for small and medium enterprises.