Labour and the Liberal Democrats spoke out after finance secretary John Swinney said the issue was “still under consideration and discussion”.
Mr Swinney said he remains keen to achieve a broad parliamentary consensus around his proposals even though, having a majority in Holyrood, the SNP government does not need to win opposition support to pass its Budget.
Last week, the Scottish Government announced extra cash for housing, job programmes and roads after looking at how it should spend additional money it will receive for 2011-12 as a consequence of Westminster spending decisions.
In the same week, the Scottish Conservatives led a debate in Holyrood calling on parliament to “condemn the Scottish Government for forcing on the [college] sector deeply damaging financial cuts”.
Party education spokeswoman Liz Smith told MSPs: “They are being asked to cope with funding cuts of £544 million to £470m, progressive cuts of £38m in year one, £50m in year two and £74m in year three.
“So by 2015 there is an annual cut of £74m.”
Mr Swinney – who will bring his Budget (Scotland) Bill back to Holyrood on Wednesday for a final vote – said he is receiving opposition “pressure” over areas such as sustainable travel budgets and college funding.
He said he was “looking carefully” at those points. “My motivation is to provide the broadest agreement,” he said. “I’m certainly open to working with the opposition parties because we made clear when the majority SNP government was elected that we would still continue to work to create consensus and agreement across the political spectrum, and that’s exactly what I’m trying to do.”
Specifically on the issue of funding for colleges, Mr Swinney said: “It’s an area that’s still under consideration and discussion, but what I would say is that there has been material change in the government’s Budget since it was announced in September.”
Scottish Liberal Democrat leader Willie Rennie said: “John Swinney has a real opportunity this week to show his support for Scotland’s colleges and reverse his cut to this sector with the extra money he has from Westminster.
“Mr Swinney says that economic growth is the Scottish Government’s number-one priority but he is choosing to cut an area that is vital for tackling unemployment.
“Scotland’s colleges help people from a range of different backgrounds get up and get on, and in this current financial climate, they are vital for Scotland’s economic growth.
“The SNP must make the right choices and support Scotland’s colleges.”
Labour MSP Ken Macintosh added: “If John Swinney is changing his position on massive cuts proposed to colleges, that is welcome.
“It shows the growing campaign from parents, students and lecturers is working.
“But he needs to act, not just listen.
“At a time when 200 Scots a day are losing their job, the last thing we should be cutting is training places for young people.
“Scotland faces the prospect of another lost generation, not just because the Tories are cutting too fast, but because the SNP aren’t putting in place the measures to stop it happening.”