The teacher unions are facing-off with the General Teaching Council for Wales over propsed changes to the organisation's membership.
The NASUWT and the National Union of Teachers want all the unions to have a seat on the profession's watchdog, as is the case on England's GTC.
Currently, the eight unions can make nominations for four places.
But the GTCW has already voted in favour of retaining its current 25-strong composition. And it wants all its members to be required to act as individuals, rather than as representatives of organisations they belong to or that have nominated them.
At present nine GTCW members, nominated by a range of education-related organisations, including the unions, are required to act independently.
Consultations on the two contradictory proposals close next Friday. David Evans, NUT Cymru secretary, said: "Because we represent so many teachers in Wales, it's important there are union voices on the GTCW to ensure the interests of their members are heard at crucial stages of decision-making in the council."
If wider union representation is agreed, then the proposal that GTCW members should act independently will have to be qualified, "because we want them to act as representatives of union members' interests", he added.
Geraint Davies, NASUWT Cymru policy officer, noted that five of its members elected to the GTCW have consistently opposed the council's professional development framework for teachers.
"They have expressed their opinions in council meetings and committees, but they have failed to carry the vote. That's democracy," he said. "If people are not allowed to express the opinions of their constituencies then it defeats the whole object."
A GTCW spokesman said the aim of recruiting members from a range of organisations was to bring a variety of views and experiences to the table.
Inevitably, members' views would be shaped by their own experiences.
But he added: "Individual union members are not there to bring their union's mandate to the table."
The consultation document proposes ways of adding union members, including increasing the size of the council from 25 to 29 members, rotating the four union seats between the eight unions, and giving automatic places to the two largest unions.
But it warns that increasing membership could add to the GTCW's costs and teachers' registration fees. It says that giving every teaching union a place "could affect the balance of the council and result in less influence from other organisations with an interest in education".
Currently, two-thirds of the council consists of members of the profession and one-third is lay.
A decision on the future composition of the GTCW is expected before Christmas, with new regulations in place by March 2007. The consultation has already delayed other agreed changes on voting categories for GTCW elections, resulting in 13 council members who were due to stand down last month being asked to serve another year.
The GTCW (Constitution) (Amendment) regulations 2007 consultation, www.new.wales.gov.uk