We will mark a very special milestone at the Association of School and College Leaders the year after next - the 150th anniversary of our organisation under the various names it has held during that long and proud history. During that time we have never, to the best of my knowledge, considered large-scale industrial action - until now.

It tells you something about the gravity of the pressures facing schools and colleges - the vice-like grip of funding shortages, pay erosion and the teacher supply crisis - that leaders, who would never normally contemplate industrial action, are increasingly of the view that a line must be drawn in the sand.

That’s why - if there is no significant improvement to teacher pay and education funding in next week’s Autumn Statement - we will launch a consultative ballot.

To be clear, this is an internal process rather than a formal ballot for action to take place.

A formal ballot has to be done according to a set of arcane rules and achieve a high threshold of support to trigger action, and we are not quite there yet. What we are doing is a step along that road in which we will ask members whether or not they want to proceed to a formal ballot on industrial action short of a strike, or strike action itself. It will allow us to gauge the level of support for such a course - and we’ll then act accordingly.

These are careful and considered steps because the notion of senior leaders taking such action is obviously a massive step. They are people who have dedicated their professional lives to educating and supporting the children and young people in their care. The last thing they want is to do anything that would be potentially disruptive to their pupils and their families. I am sure classroom teachers and other professions considering industrial action amid the cost-of-living crisis are experiencing a similar dilemma.

However, senior leaders also know - only too well - that the financial and recruitment pressures facing schools and colleges will in themselves damage children’s education. This year’s below-inflation teacher pay award after a decade of pay erosion will further impact recruitment and retention - making it even more difficult to put teachers in front of classes.

The fact that there is no additional government funding to afford the cost of this pay award will lead to job cuts. Workload will increase for remaining leaders and teachers - further damaging wellbeing, recruitment and retention. Class sizes will grow, curriculum options will be reduced, student support services will be cut.

Faced with such a bleak scenario, many may decide that the time has come to make their case with more than words to a government that has not listened so far, and does not presently show much sign of doing so. When all other options are exhausted, they may conclude that industrial action is all that is left.

What is sure is that it is the government that has brought this crisis to boiling point. It will argue that belts must be tightened in the current financial climate. But this would be easier to swallow had it not been for the long erosion of the real value of teacher pay since 2010, and the chronic underfunding of education that has run alongside this damaging policy. The government has shamefully undervalued education - and other public services - and it cannot now be surprised if it reaps the whirlwind of its neglect.

On a personal note, when I became general secretary of ASCL, I never for a moment thought that we might end up consulting on industrial action. But then I have never seen in my years of teaching and headship a time when schools and colleges have been placed in such as calamitous situation as they now face. The government has a chance to do the right thing even now. It must invest in teachers, invest in education and invest in the future.

Geoff Barton is the general secretary of the Association of School and College Leaders