Nicola Sturgeon has attacked Liz Truss for failing to telephone her since she became Prime Minister, arguing the snub was “absurd” and “unprecedented”.
The First Minister questioned whether the “unprecedented” lack of a phone call since the Truss premiership started on Sept 6 was down to “arrogance, lack of respect or insecurity”.
She held talks with Theresa May and Boris Johnson shortly after they became prime minister and argued that Ms Truss failing to follow suit was “not the right way to do government in a grown-up way”.
The Prime Minister branded Ms Sturgeon as an “attention seeker” who was best ignored during the Tory leadership contest.
Ms Sturgeon’s intervention came ahead of the start of the SNP conference in Aberdeen on Saturday, which the party’s deputy leader will open with a claim that Ms Truss is a worse prime minister than Mr Johnson.
Keith Brown will tell delegates that the economic turmoil that followed the mini-Budget showed she was “singularly unfit for the job” and predicted “it won't be long” before the Tories oust her.
But Mr Brown is expected to reserve his most outspoken attacks for Labour, amid predictions that a UK Government led by Sir Keir Starmer would damage support for independence.
The SNP depute leader will say that Sir Keir is “just another Tony Blair” and argue that separation is “Scotland’s only chance to escape Tory chaos for good”.
In an interview with the BBC, Ms Sturgeon said that she had had no contact with Ms Truss other than “an exchange or two” at events following the death of the Queen.
“I don’t know whether that is arrogance, lack of respect or insecurity or whatever it is. It’s not the right way to do government in a grown-up way,” she said.
“So I hope we will see a change. I’ll do my best to work with Liz Truss as constructively as possible or whoever comes after because we can’t take anything for granted in UK politics these days.”
Ms Sturgeon said Mark Drakeford, her Welsh counterpart, had also had no contact from the Prime Minister.
In his opening conference speech, Mr Brown will say: “What is clear is that Liz Truss is a symptom of the dysfunction at Westminster – not the cause. The very fact that she and her policy agenda was deemed acceptable to enter Downing Street in the first place speaks volumes.
“And, conference, as bad as the Tories are – and they are atrocious – any suggestion that a Labour Westminster government will be better for Scotland is simply laughable.”
He will add: “We know through the bitter lessons of history that Labour are only ever the handmaidens of more Tory rule.
“If they get into power, they are soon turfed out by the Tories and gift to them the same powers of Westminster control they always abuse. It’s a pattern repeated time after time after time.”
But Jackie Baillie, Scottish Labour’s deputy leader, said: “There you have it in black and white – the SNP do not care whether the next UK government is run by the disastrous Tories or a reforming Labour government.
“It is clear for all to see that the SNP’s claim to be a progressive party is a sham. They don’t care about kicking out this disastrous Tory government, all they care about is their narrow nationalist obsessions.”
A UK Government spokesman said: “The Prime Minister has made clear the UK Government’s priority is to deliver economic growth across the union and to work together on shared issues including energy security.
“UK Government ministers, including the minister for intergovernmental relations, along with officials, are continuing to engage regularly with their devolved counterparts.”