Scotland's First Minister has said he is "not interested" in a fight with the UK Government over his plan to cap essential food prices.
John Swinney unveiled his party's manifesto in Glasgow on Thursday, including a plan to limit the cost of up to 50 essential items.
Within hours, a senior UK Government source said the proposal is "undeliverable" and would result in millions of pounds in legal bills.
I need the UK Government to be rational and considered about policy proposals that will help members of the public overcome the challenges that they face in their daily lives
John Swinney
The plan would be instituted using the Scottish Government's powers over public health, but could be scuppered if Westminster finds it does not meet the terms of the Internal Market Act.
A decision to block the plan - which would be tabled in the early days of an SNP administration if John Swinney is to win on May 7 - could be politically advantageous for the First Minister, allowing him to claim the UK Government is stopping him from reducing people's bills.
But speaking to BBC Radio Scotland on Friday morning, Mr Swinney said he is not looking for a political scrap with Westminster.
Asked if he is looking for a fight, he said: "Not in the slightest, I'm not interested in that in any way, shape or form.
"I'm interested in making sure that I deliver practical help for families."
He went on to suggest the Labour-led UK Government could be acting politically by criticising the plan.
"The UK Government is not a disinterested bystander, they're not really dispassionate," he said.
"They're a Labour Government that is up to its neck in scandal.
"I need the UK Government to be rational and considered about policy proposals that will help members of the public overcome the challenges that they face in their daily lives.
"That's what I'm unrelentingly focused on, is the challenges that people are facing because of the cost of living and doing everything I possibly can do to help them out.
"There's a range of measures we're bringing forward, all about making sure that we take the action we can within our responsibilities, and the UK Government shouldn't be an obstacle to the Scottish Government achieving our objectives."
In a statement hours after Mr Swinney first announce the plan, a UK Government source did not say it would be blocked, but said: "This is an incoherent and undeliverable policy that risks costing the Scottish Government millions in legal bills.
"John Swinney has invented a policy more likely to put money in the pockets of lawyers than the pockets of working people.
"The UK Government is focused on taking immediate action on the cost of living - like cutting fuel bills now."
It is understood the SNP is prepared to fight supermarkets in court over the plan, though a multi-year case against retail giants would likely be expensive.
The SNP manifesto, which also includes plans to cap bus fares at £2 per journey and a commitment not to raise income tax, is made up of "bold ideas", the First Minister said.