Up to 2,000 students in Wales have joined a demonstration in London over UK government plans to raise tuition fees and cut education budgets.
Fees for students from England studying in Wales may rise to a possible £9,000.
The assembly government estimates it would also cost an extra £70m-£110m a year to fund Welsh students on courses in England.
The UK government says its plans are "fairer" than the current system.
Cardiff University students' president Olly Birrell said the cuts were "too deep, too vast, too quick - and that students won't take it".
"I think the main concern is the cuts, because the cuts are what leads onto the rise in tuition fees," he said.
"But I think the anger is very much for both - but the cuts is the main aim of this demo."
Wednesday's demonstration in London was called by the National Union of Students and the University and College Union.
In all, Welsh colleges said they were sending about 25 coaches to the protest from across Wales.
The president of Bangor University's students' union, Jo Caulfield, said: "We are now a few years down the line from when they raised fees from £1,000 to £3,000, and yet we've seen no significant increase in student satisfaction over that time.
"Now they want to treble those fees and we would like to see a justification for that, before that happens.
"We are there to try to make our case, to say that education is important and should be a right for everybody."
The UK government announced plans last month to raise fees for students in England to a maximum of £9,000 per year, with universities facing obligations to act to recruit more students from disadvantaged backgrounds if they want to charge more than £6,000.
At present in Wales fees are capped at £3,290. Until 2010-11, all Welsh students studying in Wales were given a grant of £1,890 towards their fees.
The UK government says the proposals will protect poorer students and are designed so that better-off graduates pay higher contributions.
"Access to higher education will be on the basis of ability, not ability to pay," said a spokesperson for the Department for Business Innovation and Skills.
"The graduate contribution system will protect the lowest earning graduates and ensure that their contributions are linked to their ability to pay."