Labour councillors have demanded an apology from South Lanarkshire’s SNP group in an increasingly bitter war of words over last month’s local authority budget.

The SNP minority administration failed to see its budget proposal passed two weeks ago, with Labour’s amended budget ultimately approved instead.

The main difference between the two bills was that the SNP version proposed extending the option of free school meals across all Primary 4 and Primary 5 children, whereas the Labour version wanted to introduce the free at three education scheme a year early.

In the aftermath of the budget, several nationalist councillors took to Twitter and social media to attack the decision, accusing Labour of being “dinner snatchers”.

Those comments and claims prompted a furious response from Labour representatives, again via Twitter.

And now the Labour group has demanded a formal apology, saying the claims “misrepresented” the budget proposals and are tantamount to “appalling scare mongering”.

Councillor Lynsey Hamilton, Labour’s education spokesperson, said: “This desperate propaganda from the SNP in South Lanarkshire is irresponsible and alarmist.

“Nobody who receives free school meals will see them stopped or taken away and any suggestion that they will is utterly misleading and untrue.

“There should always be a place for robust debate in politics but never for appalling and reckless scaremongering like this.

“The SNP should issue a formal retraction urgently and any SNP councillor who has made inaccurate statements about school meal provision or shared misleading material on social media should publicly apologise.”

In response, SNP councillor Katy Loudon said: “Labour joined with the Tories to stop 6000 children in our primary schools getting a free meal at lunch-time.

“Instead of trying to spin their way out of that decision, Labour should apologise for playing political games at our school pupils’ expense.”

Among the Twitter comments that caused the row was SNP council leader John Ross’ statement: “Never forget that the only ‘victory’ the Lab-Cons can really claim is that they stopped us giving free school meals to all eight and nine year olds.

“No-one will be surprised to see the party of milk snatcher Thatcher doing that.

“But for their Labour allies to do that – in open mockery of their party’s manifesto claims – is a disgrace that should never be forgiven.”

Rutherglen’s SNP MSP Clare Haughey wrote: “If you wanted proof that @scottishlabour collude with @ScotTories against @theSNP trying to tackle child poverty here you have it.”

Labour politicians responded in equally strong terms. Joe Fagan, the party’s local group leader, wrote: “How about writing to your own SNP government and asking them to give the council a fair budget deal so that we don’t have to choose between free childcare or more free meals?

“Stop posturing and start leading.”