Labour Relations Commission Chief Executive Kieran Mulvey has said he does not understand the decision of two teachers' unions not to ballot their members on the Haddington Road Agreement.

The Association of Secondary Teachers of Ireland and the Teachers Union of Ireland said they had taken the decision because they believed the proposals on public sector pay did not contain sufficient improvements on what was allready on the table.

In an interview on RTÉ Radio, Mr Mulvey said the decision would look odd whatever the outcome of the deliberations by the ASTI and the TUI.

"They haven't said no. They just said they wouldn't ballot their members on whether they should said yes or no,” he said.

"So I must say I'm quite mesmerized by that decision because the fundamental role of any trade union is to consult with their members and to ask their opinions.

"They say it's not a materially different set of proposals; I think they are.

"It will look strange, I think, in the firmament of industrial relations and collective bargaining if actually union members don't vote."