The Browne review of higher education funding in England could have "calamitous" consequences in Scotland, the Educational Institute of Scotland fears.
The union has warned that a free market model and unlimited tuition fees south of the border would pave the way for a cut in the Scottish Government's block grant and, as a result, reduce its ability to fund universities.
The recommendations by former BP chief executive Lord Browne envisage a 10 per cent growth in student numbers at English universities, but the EIS says this would allow the Westminster Government to reduce its funding of English higher education and shift the burden from the state to the individual.
This, argues the union, may provide a pretext for reducing the Scottish block grant as determined by the Barnett formula, which passes on Whitehall spending decisions to the devolved governments.
A spokesman said: "If such a cut were passed through to Scottish universities and higher education institutions, the effect would be calamitous. The EIS fears that to offset such a cut, Scotland will be forced to adopt some form of tuition fee or graduate tax, both of which the EIS currently opposes.
"The Browne review may, therefore, lead to far-reaching consequences in Scotland as well as south of the border."
UK Business Secretary Vince Cable last week backed Lord Browne's findings and said that, in Scotland, "realities are going to have to be faced".
Upfront tuition fees continue to be anathema in Scotland, but Education Secretary Michael Russell is under pressure to find an alternative which would allow universities to remain competitive without imposing excessive charges on students.
He has ruled out upfront fees, but promised to consider "all sensible ideas, no matter how radical". A green paper will be published in December, although changes to the system would be unlikely to apply until 2012-13 at the earliest.
Universities Scotland has warned that any wrong moves over the coming weeks - as the implications of the UK Government's comprehensive spending review and next month's response from Scottish Finance Secretary John Swinney become clear - could "irreversibly damage" higher education north of the border.
Work on longer-term funding should not distract politicians from setting a budget that enabled universities to continue making a central contribution to Scotland's economy, Universities Scotland convener Bernard King insisted.
"It will be at least two years before it's technically possible to implement a long-term funding model for Scotland's universities," he said.
"In that time, more than a quarter of a million students will have gone through Scotland's universities. Those students are entitled to demand proper investment in their education right now."
Universities had already found large savings and were looking for more, Professor King stressed. Like many in Scotland, he believes a contribution from graduates is necessary to shore up higher education funding.
- Original headline: Fears over the `calamitous' results of Browne review