The price tag suggested for adding more foreign languages to the school curriculum is just a "drop in the ocean", according to a teachers' union.
The Scottish Government's ambition for piloting languages in primary school is to be welcomed but ministers must be realistic about the scale of the challenge, the Educational Institute of Scotland told MSPs investigating the plan at Holyrood.
The Government has said it would provide £120,000 to fund pilot projects and an additional £4 million in 2013-14 to support councils.
Hugh Donnelly, member of the union's education committee, said: "I think the £4 million is a drop in the ocean. I think also the scale and ambition did surprise a lot of us in education."
The SNP wants to introduce at least one second language from the first year of primary school. The exercise would be tested in selected schools across Scotland.
Mr Donnelly said: "The upbeat thing about this project is that we're beginning to look at this afresh. It is a big opportunity to stop the rot and actually to build a base for the future. I'm not being pessimistic, I am being realistic. If we achieve progress from these recommendations, I think that will be a fantastic thing. The better the progress, the more sophisticated the progress, the better resourced it is, the happier I will be."
But there are competing demands across subjects. "I bet no one has put a figure on what is absolutely necessary," he said. "These questions are important and we need to move forward with clarity."
Schools are already having to deal with cutbacks, MSPs on the European and External Relations Committee were told.
Mr Donnelly was joined by members of the Association of Heads and Deputes Scotland and the National Association of Schoolmasters Union of Women Teachers at the committee meeting. MSPs asked the EIS to come back with their own suggestion for the cost of the proposal.
A Scottish Government spokeswoman said: "We are funding 10 pilot projects in primary and secondary schools across Scotland in the current school year to demonstrate how this can best be delivered, and we will work with local authorities to apply the lessons learned. In addition, we are committed to providing £4 million in the next financial year to local authorities as part of this long-term commitment which is being implemented over two parliaments."