Substitute teachers who are members of the ASTI say they are finding themselves impacted because of the opposition by the union to the new Junior Certificate cycle.

ASTI members are barred from taking part in training for the new programme.

But secondary teachers attached to the TUI do participate.

Noel Hogan is a substitute teacher, currently teaching History and Geography at St Louis Secondary School in Carrickmacross in Co Monaghan.

He told Newstalk Lunchtime he thinks it will have a direct effect on his career prospects.

"If I go for work from this summer on because of these directives, I'm going to be disadvantaged when it comes to interview" he said.

"I mean if you were a principal and you had a choice between me - who can't do the training because of a directive - or a TUI member who can, who would employ" he added.