Department of Education has confirmed that an undisclosed number of ASTI members have contacted its wages section about cancelling union subscriptions.
A spokesman said he could not reveal how many teachers had been in contact, but many raised the issue in recent days. The Department automatically deducts the subscription for the union.
He said the Department was obliged to cancel a subscription if requested. The teachers are understood to have sought this because they are unhappy with the way the union has handled their pay claim.
These teachers, many of them in Dublin, and some of them on the union's executive, are seeking to put pressure on the union's head office. However, it has warned them that an ASTI decision some years ago means they have to have subscriptions deducted at source.
Several teachers who have contacted The Irish Times said they wanted to be responsible for the subscription themselves, rather than have it paid automatically.
However, a spokesman for the ASTI said "whole branches" had not left the automatic system although up to 20 queries had been received about the possibility.
Some teachers are concerned the Department might use the system to identify them as ASTI members during any work-to-rule.
An ASTI statement said: "An article in yesterday's paper stated that whole branches of the ASTI have pulled out of the ASTI membership subscription process whereby subscriptions are automatically deducted from members' salaries. This is incorrect. No branch has pulled out of this system.
"Over the past number of months, up to 20 members have inquired about paying their subscriptions by other means and they have been advised by the ASTI's membership department that under ASTI rules adopted by convention, members who are paid by the Department of Education and Science must have their subscriptions deducted directly from their salary."