Waiting to assess the impact of funding reforms on postgraduate study would be a "huge error of judgement", as university courses cannot be turned on and off like machines in a factory, the new chair of the 1994 Group has warned.
Michael Farthing, vice-chancellor of the University of Sussex, said it could take years to re-establish master's courses if they are wiped out by falling demand, and he argued that urgent action was needed to prevent such meltdowns.
In an interview to mark the start of his tenure as chair of the group of smaller research-intensive universities, Professor Farthing said there was already a noticeable schism in fee-setting among institutions nervous about the future.
While some felt postgraduate fees needed to be much higher, he said, others were "hedging" and keeping charges steady as they waited to see "how big the disaster is going to be".
The government pledged in its higher education White Paper to keep the postgraduate issue under close review and revisit funding as the new undergraduate system "beds in". But Professor Farthing warned that the government was being far too blasé.
"If you've got a machine making widgets, it is very easy to turn that machine off and stop making widgets," he said. "If we turn off taught postgraduate programmes...it isn't just a question of turning the electricity back on. The development time to re-establish those programmes is years, not weeks or months."
He added: "I think we're going to face a real crisis because universities currently have struggled to decide what their fees should be because nobody knows what's going to happen to applications."
Professor Farthing also warned that a relative decline in the number of home postgraduates - both taught and research - was threatening the UK economy.
In postgraduate research, he said, more students in the country now hail from outside the European Union.
A decade ago this may have mattered less as they often stayed on after their studies. However, students from emerging economies such as India and China increasingly are returning home to help fuel growth there rather than in the UK.
He called for "serious incentives" to be established to encourage home students to progress to doctoral programmes, adding that all research-intensive universities "should be speaking with one voice on the issue".
Professor Farthing's comments on postgraduate education came as the head of England's funding body said that the issue may need more "urgent" attention than the government has been suggesting.
Sir Alan Langlands, chief executive of the Higher Education Funding Council for England, told the organisation's annual meeting earlier this month that it was likely that "policy interventions" would be needed sooner rather than later.
"I don't think we can wait, as the White Paper kind of asks us, to monitor the position over the next few years," he said.
Meanwhile, in a wide-ranging interview, Professor Farthing, a medic who specialises in gastroenterology, also told Times Higher Education that the government should focus on boosting international research collaboration as a way to drive domestic growth.
"One of the areas that I think the UK could develop further is...international consortia for research. The UK is losing out...to places such as China and India," he said.
The vice-chancellor also reiterated the 1994 Group's belief that ministers should quickly lower the grade threshold at which student places are opened up to full competition. Currently it stands at AAB at A level.
And he suggested that the government may have "underestimated" the number of AAB students in the sector in 2012-13 because of the way the numbers were measured.
At Sussex, when analysts had "cleansed the data", they found the institution was in a "much more favourable position" in terms of AAB numbers than had been suggested, Professor Farthing said.