A leading union for teachers has called for Sammy Wilson to apologise after the DUP MP said they "seem to find a thousand difficulties for every solution over plans to reopen schools in September".
And he accused the union of putting jobs at risk if people can't go back to work because their children are unable to go back to school.
A war of words has now erupted with NASUWT national official for Northern Ireland Justin McCamphill over the comments that were made after Education Minister Peter Weir published his New School Day guidelines last week.
The East Antrim MP said: "There has been a distinct difference between what happens at ground level where teachers have been creative, innovative and energetic and the whingeing by some of the leaders of the trade unions who seem to find a thousand difficulties for every solution.
"If they are offended by the comments, they are meant to be. If it has made them angry, it was meant to.
"The unions owe their own members an apology for giving teachers a bad name in the eyes of parents.
"Their actions imply that teachers will do anything they can to avoid going back to work. Before Covid-19 we were told teachers would not be dictated to by the department. Now the department is being asked to lead the way.
"All through this I have been involved with various sectors who have all provided ideas, while education has been sitting waiting for a prescriptive answer. But no two schools will be the same.
"In the end this will not only affect the education of children, it will affect the economy too if parents can't go back to work. Part of the responsibility for that will be blamed on the unions."
But Mr McCamphill hit back, claiming that Mr Wilson was deliberately trying to pitch parents against teachers.
"All he is doing is undermining the profession and his own colleagues," he said.
"It appears that the DUP and Peter Weir have oversold what is going to happen in September. On Thursday they announced that all pupils would be returning, but when the guidance came out on Friday it's quite clear they are working within the scientific advice that they have and that not all pupils will return.
"That guidance was drawn up after discussion with teachers, so how he can say teachers haven't provided ideas is nonsense. In my view it's a one-sided attack on teacher unions. I don't believe the majority of DUP MPs would even share Sammy Wilson's theory and I believe he's doing this to the detriment of his own party.
"We have looked at the guidance. Bits of it are good. Bits of it we're sceptical about. Teachers are going to put that guidance into place and us as a union will protect our members. Where we're not happy with it we will question.
"Sammy Wilson should apologise to the teaching profession for the comments he has made about them. If he doesn't we'll ignore him. Teachers will make up their own minds."