Education and health ministers want to place a new duty on Scottish local authorities to step up the number of meals taken in schools and to ensure the anonymity of those taking free meals - despite admitting that schools may not be able to cope.
However, despite widespread public pressure there is no provision in the Schools (Nutrition and Health Promotion) (Scotland) Bill, to make free meals universal, even in primary schools.
This is the key demand from groups such as Child Poverty Action Group, One Plus and the Poverty Alliance in its rival free school meals and snacks bill. The Association of Heads and Deputes in Scotland, representing primary schools, also supports universal provision of free meals.
Aside from the cost, estimated at between pound;177 million and pound;222 million for providing the meals alone, another key factor may be that many schools simply do not have the capacity to serve all their pupils at one sitting.
A consultation document launched this week hints that even expanding current uptake, which costs pound;59.5 million a year, might be problematic and entail capital costs. "The capacity of school catering facilities to cope with increased numbers is not fully quantified," the document states.
"In many cases, local authorities will be unable to meet increasing demand for meals without further investment being made into expanding catering facilities or by holding more than one sitting for lunch each day."
The document says that authorities will have to rely on the current pound;2 billion programme - involving the "largest ever investment in school buildings" - to meet those costs and should not expect additional funding.
The Scottish Executive says that it has explored the option to provide universal school meals but adds: "We do not consider this an effective way in which to achieve our goals of improvements in diet and health and at the same time target inequalities."
Instead, ministers wants to target children and families most in need while continuing to consider options to extend free school meal provision.
The current rate of uptake for school meals is 47 per cent of all pupils.
In 2005, 19 per cent of pupils were entitled to free meals and some 67 per cent of those who were eligible took a free meal on the day of the survey.
This indicates that about 12 per cent of all pupils took free meals.
But there are huge variations among authorities. In secondaries, for example, the proportion of those entitled to a free meal who actually took one ranged from 56 per cent to 100 per cent.
Ministers also want to ban the sale and availability of "junk" food such as sweets and fizzy drinks on school premises. This duty would extend to children whose places at independent schools are funded by local authorities.
Councils would also be given new powers to provide children with drinks such as water or milk, and fruit, vegetables, bread or cereal-based snacks at any time - with or without charge - thus extending the principle of free lunches to free breakfasts and mid-morning snacks.
Scottish ministers and local authorities face another new duty of endeavouring to ensure that all local authority schools become health-promoting by 2007.