A call has been made to delegates at the ASTI's annual conference for the infighting in the union to stop and for an open debate on whether ASTI should join the Sustaining Progress negotiations.
The call was made by the acting general secretary of ASTI, Mr John White, who said "society needs a unified, coherent organisation to represent teachers".
The country's largest second level teachers union has seen a bitter battle waged within its ranks over the last four years on how to negotiate its pay claims. The union also does not participate in the next rext round of pay talks under the Sustaining Progress partnership deal.
"It is time to go forward with a sense of unity and a sense of coherence and two argue our case and get broad community support. It's not in the interests of the Government, it's not in the interest of society that second level teachers are not represented by a coherent organisation where everybody is pulling together," said Mr White.
He added that issues to do with personality and internal wrangling had no place in policy focused issues.
On the issue of rejoining the Irish Congress of Trade Unions (ICTU) Mr White said: "We should debate the whole issue of whether it is better to go with a range of colleagues to pursue our goals or whether we feel that can pursue them better on our own and that discussion should take place without rancour".
He said he believed there would be a time when the ASTI rejoined ICTU.