Opposition parties have defeated the Welsh Assembly Government in a debate on university tuition fees.
The Rees report has not looked into scrapping tuition fees
Assembly members voted by 30 to 29 in favour of a Welsh Conservative motion not to introduce top-up fees in Wales.
Labour AMs had criticised a decision to go ahead with the motion before the publication of the Rees report into higher education funding.
But opposition members accused Labour of ignoring what they said was the will of the majority of the assembly.
The vote came two days before the publication of an independent report outlining future funding options.
Following the defeat, the Welsh Assembly Government said in a statement: "The government will of course have to consider the implications of this vote very carefully.
"We remain committed to developing a system of higher education funding that that is fair to institutions and to students.
"We are confident that the Professor Rees report, when it is published later this week, will provide an invaluable evidence base on which to respond to those twin commitments."
Speaking after the vote, Nick Bourne, leader of the Conservatives in the assembly, said AMs had now "spoken clearly and unambiguously" on the issue of top-up fees.
REES REPORT OPTIONS
1. £2,000 fixed fee
2. Market-driven English competitive model: top-up fees up to £3,000
3. Assembly government part-managed scheme: top-up fees up to £3,000
4. Maximum £2,000 fees for Welsh students; up to £3,000 for non-Welsh students
5. £3,000 fixed fee
"Welsh Conservatives have consistently opposed top-up fees and it is now up to Rhodri Morgan to bring forward fresh proposals as to how this vote can be honoured.
"Labour has badly misjudged this issue and has failed the people of Wales by not honouring a commitment never to introduce top-up fees. They must now think again."
Labour lost its assembly majority when AM Peter Law left the party to stand against it in the general election.
Mr Law, standing as an independent candidate, won in the recent general election to become MP for Blaenau Gwent and voted against Labour on Tuesday.
He said: "Rhodri Morgan...has not stood up and said 'we will not have top up fees' and that's the mistake.
"Where's the principle from the Labour movement to allow people to have the right to free education?"
Ieuan Wyn Jones, leader of Plaid Cymru in the assembly, said all the opposition parties did not want to see top-up fees introduced in Wales, and the Labour administration needed to realise it no longer had a majority.
"They have to realise the game has changed and they have to take on board the views of other people," he said.
And Liberal Democrat leader Mike German suggested Mr Morgan needed to change his approach.
"What he should be doing is recognising he is now in minority and should be talking to the opposition parties more about the policies he intends to bring forward."
'No debate' plea
Tuesday's motion was proposed by the Conservatives.
The wording of the motion was: "The Welsh Assembly Government is instructed not to introduce top-up fees in Wales and to ensure that Higher Education Institutions are fully funded."
Last week in an unprecedented move, Professor Teresa Rees, chair of the special commission which compiled the report, wrote to all AMs asking them not to hold the vote until after her research was published.
A interim version of the Rees report, published in March, set out possible ways of imposing top-up fees after the next Welsh assembly elections in 2007.
Speaking on the BBC Wales Dragon's Eye programme, Prof Rees ruled out the status quo of a flat fee which is expected to be £1,200 in the next academic year.
All UK students are currently charged the flat fee with part or all of the cost met by a local education authority for those from low-income families.
A variable top-up fee of up to £3,000 is to be introduced in England in 2006.
A similar system was among the six options in the interim report.
In the assembly, Education Minister Jane Davidson criticised the opposition for going ahead with the motion before the publication of the Rees Report.
She added: "We have not made our position clear on how we want to move forward because we want to look at the evidence.
"I believe that if we were not to take that view, to have a debate on the basis of resolutions which have to amended because they are not quite right...is not the right environment to have a debate on this issue."