The government last night insisted it was winning the battle over extending free school meals, claiming that increasing numbers of local authorities were signing up to the scheme.

Citing developments at Fife, Falkirk and North Lanarkshire councils, it was claimed that the tide had turned and councils were increasingly pleased to associate themselves with a policy due to come into force in almost two years' time.

Ministers refused to back down over the issue. "We are confident we will win this argument," said a senior Salmond aide. "They said we would never get the council tax freeze, now they are saying we won't get the extension of free school meals. "

The plans came under fire from Labour opponents over funding.

The First Minister faced a grilling on the issue in parliament, while it also reared its head in the Glenrothes by-election campaign.

Council leaders are meeting today after weekend claims that some councils had expressed concerns about how they would finance the scheme. Labour's Karen Whitefield, who convenes Holyrood's Education Committee, raised the issue during First Minister's Questions.

"More than half of Scottish councils have publicly said that they can't afford to provide free school meals within their existing resources," she said, and asked: "Which education services will be axed to pay for free school meals?"

Ms Whitefield queried how councils can "possibly have sufficient funds" when the cost of implementing the policy is "variable and dependent on specific local circumstances" according to the Scottish Government's own report.

The First Minister said all SNP-led councils will be implementing the free school- meals policy and added that independent councils in Orkney and Shetland also supported the programme. "With that cross-party enthusiasm, I wouldn't like Karen Whitefield and the Labour Party to be the only party in Scotland trying to take the meals from the mouths of Scotland's children in 2010," he said.

Labour's Glenrothes candidate Lindsay Roy, a local head teacher, called for ministers to fund the policy in full, amid Labour claims that SNP-run Fife Council had failed to find the money for the scheme.

But council leader Peter Grant, the Nationalists' candidate for the seat, later said the council intends to implement the policy in full.

Tory Liz Smith said the SNP can not have it both ways on the issue. "You can't try to force councils to adopt government one-size-fits-all policies on class sizes or free school meals and, at the same time, tell them they are free to adopt their own priorities," she said.

"Scottish Conservatives have long been arguing that the SNP's flagship policies for schools are simply not deliverable."

Nationalist back bencher Alex Neil said Labour-led Falkirk council confirmed the money to fund free school meals has been received from the Scottish Government. and added that local councils had also received a significant increase in their funding from central government.