Barry Gisbourne, a retired media and business studies teacher from Shaftesbury, Dorset, said: “Merging the unions is a great idea but I don’t think it will ever happen. If we could speak with a unified voice we would have far more impact. The problem is that we could never work with certain factions of the NUT who insist on putting political interests above educational ones.”

Ray O’Neil, a science teacher from Isleworth and Syon school in Hounslow, London, said: “I think a merger would be a dreadful idea. Although there are situations when we could work together, there are several core differences. The NASUWT is the only union that spends more time taking action rather than talking about it.”

Christina Castle, of the NASUWT, a design and technology supply teacher from Gloucester, said: “I think one union would be too big and unwieldy and I would be amazed if they did ever merge. It is easier to steer three small boats than one big tanker. I would prefer to see co-operation rather than a total amalgamation.”

Jayne Jones, of the NASUWT, a special needs teacher from Darland High school, Wrexham, said: “We are very different breeds and I can’t see how we could join together totally. All the different unions reflect the diversity of the profession and that is god. But I do think we should work far more closely with the other unions on certain key issues on which we all agree, such as campaigning for a new contract for teachers, because that gives us a far more powerful voice.”

Adrian West, a French teacher from Prestatyn high in Denbighshire, said: “I think the theory behind a merger is fine but more difficult in practice. The NASUWT, for example, has always been more proactive in taking industrial action, while the Association of Teachers and Lecturers has been a virtual stranger to it.”

John Bills, former NUT president, said: “We are closer than we have ever been since I joined the NUT to professional unity. We have had joint action with NASUWT and their president has addressed our conference and been well-received, as has the general secretary of ATL. One union for teachers in England and Wales will be the best way forward for teachers in England and Wales. Governments have always been able to divide teachers.”

Anne Moran, former NUT treasurer, said: “We have taken so much joint action now it’s nonsense to pursue different directions. At school level, teachers want the same thing. I think there will be a single union, but it’s difficult to say when - we could be looking at three or four years. I’m convinced that teachers want it but the Government doesn’t.”