Labour MSP Cathy Jamieson says the plan for P1, P2 and P3 pupils would land cash-strapped South Ayrshire Council with a huge financial burden that must have an impact on existing budgets for vital services.
But her SNP and Conservative colleagues, Adam Ingram and John Scott, have welcomed the Scottish Government initiative and claim that the success of pilot projects in other parts of Scotland added up to healthier eating habits throughout the education system.
According to Ms Jamieson the scheme, due to start in August 2010, could cost up to £50 million a year across Scotland.
And she said: "This announcement by the SNP Government will put severe pressure on the Tory/SNP coalition at South Ayrshire to find the cash to pay for free school meals.
"The Education Secretary, Fiona Hyslop, is demanding this initiative without providing the money to pay for it. Local authorities are already struggling to employ newly qualified teachers and reduce class sizes."
Ms Jamieson added: "I would like to know how South Ayrshire SNP councillors can explain away more promises made by their government in Holyrood that leaves them in the lurch.
"They will have to find more money to pay for free school meals from budgets that are being squeezed on all sides.
"Fiona Hyslop is shirking her responsibilities and passing the buck to her local colleagues and their Tory coalition partners."
However, Minister for Children and Early Years Mr Ingram cited the success of pilot programmes involving 35,000 children in West Dunbartonshire, Borders, Fife, Glasgow and East Ayrshire.
The conclusion was that uptake of school meals among P1s to P3s rose from 53 per cent to 75 per cent. Within the target group of pupils not registered for free school meals, uptake increased from 41 per cent to 69 per cent.
Said Mr Ingram: "The concordat between the Scottish Government and Convention of Scottish Local Authorities stated that if the evaluation of the trials were positive, legislation would be introduced to allow extension of the nutritious free school meals to all children in P1 to P3.
"The evidence from the evaluation work carried out during the pilot clearly indicates the scheme was a success and I am sure this announcement will be welcomed by the pupils, parents and carers in South Ayrshire.
"This Government has made it a priority to help children in their early years and this initiative does just that, providing every child with a free school meal in their first years at primary school."
Research conducted during the pilot programme found that the trial resulted in significantly increased uptake of school meals. Among the target group of P1-P3 pupils who were previously free school meal registered, it rose from 89per cent to 94per cent and among P4-P7 pupils, 47per cent to 50per cent.
Some pupils taking part in the trial were trying and enjoying new foods and asking for healthier options at home.
Under the agreement with COSLA, the two-year timetable will give local authorities time to carefully plan for the introduction of free school meals, learn from the areas which piloted the scheme and negotiate contracts with suppliers.
The Children's Minister added: "The Government are committed to tackling obesity and unhealthy eating habits at a young age and are working with CoSLA to deliver positive changes for Scotland's children.
"As part of Scotland's first-ever national food and drink policy, the Government are encouraging all Scots to develop healthy eating habits that will benefit them for the rest of their lives and help tackle the serious problem of obesity.
"The pilot gave pupils an opportunity to try new healthy foods with some asking at home for foods they had tried at school. Parents also reported talking about food with their children more often and some said their children were more confident in discussing their food preferences.
"Now every child in those vitally important early years in South Ayrshire will have the opportunity to enjoy these same experiences. Parents too will feel the benefit during these financially difficult times."
Giving his support to the scheme Mr Scott, the Scottish Conservatives' rural affairs spokesman, said: "The stark evidence is that far too many pupils in Scotland miss out on being able to access regular and healthy school meals, so any measures we can take to improve their chances is to be warmly welcomed.
"The roll out of a national scheme will undoubtedly go some way towards addressing this issue, and I am delighted that South Ayrshire Council has confirmed that they are committed to pushing forward with this policy.
"This is a welcome step and I look forward to progress being made on providing healthy, nutritious meals to all local Primary 1 to Primary 3 pupils, and to the long-term benefits that this will bring in terms of their health, education and wellbeing."
Confirming South Ayrshire's commitment to delivering the free school meals policy, council leader Hugh Hunter said: "As part of the concordat signed between ourselves and the Scottish Government, South Ayrshire Council agreed to implement a free school meals policy for all pupils in primaries 1 to 3, as from August 2010.
"We regard meeting this objective as a key priority and it will form part of our budget discussions over the coming months."
Another 'plus' for last week's announcement came from John Dickie, head of the Child Poverty Action Group in Scotland and a leading member of the Free School Meals Campaign.
"This is a massive step forward in the campaign to ensure every child, whatever their home circumstances, gets a healthy meal at school," he said.
"We in the Scottish Free School Meals Campaign urge Parliament to support the roll-out of this excellent initiative to all Primary 1 to 3 pupils. It will help boost children's health, education and wellbeing and provide a really welcome benefit to hard pressed families across Scotland."
During the eight-month pilot programme Mike Gibson, of the Scottish Government Schools Directorate reported: "We have estimated that, if free school meals were rolled out to all primary 1 to primary 3 pupils, it would cost roughly from £30 million to meet the bottom line 70 per cent uptake to £46 million for 100 per cent uptake."
At current rates of pay, £46 million would provide 1,543 new, grade 1 teachers.
The evaluation report and a four-page Research Findings will be published on the government website at http://www.scotland.gov.uk/Publications/2008/08/29114033
and http://www.scotland.gov.uk/Publications/2008/08/29113958
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