Liz Truss is yet to pick up the phone to speak to Nicola Sturgeon a month after taking office in an "absurd" snub, the Scottish First Minister said.
Ms Sturgeon said she has yet to have a proper call or a meeting with the new Prime Minister, who famously dubbed her an "attention seeker" who should be ignored during her leadership campaign.
The First Minister fumed: "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."
In an interview with the BBC, she said that she and Ms Truss had spoken at events marking the Queen's death, but have yet to have an official chat about political business.
Ms Sturgeon said: "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.
"I spoke to (the PM) David Cameron when I became First Minister within hours.
"I spoke to Theresa May and Boris Johnson shortly after they became prime minister. For reasons best known to herself, Liz Truss hasn't engaged with the devolved administrations."
The First Minister said the lack of an official meeting is "absurd".
She said: "I'll meet with her, I'll speak to her, but let's just underline how absurd it is that a UK Prime Minister doesn't seem to want to work with - other than in rhetoric - the devolved administrations in the rest of the UK."
Ms Truss famously sparked ire over the summer when she claimed the Scottish leader should be "ignored".
Ms Sturgeon said during an appearance at the Edinburgh Festival Fringe the only conversation she had with Ms Truss was at Cop26 in Glasgow, where she claimed the then foreign secretary asked her how to get into Vogue magazine.
A spokeswoman for the UK Government 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."
Elsewhere Ms Sturgeon said the Scottish Government will publish a new paper setting out its plans for the economy and currency of an independent Scotland next week.
Speaking ahead of the SNP conference, the First Minister told BBC Radio Scotland the paper would be released days after the party gathering and after arguments are made at the Supreme Court that could allow her Government to legislate for a second referendum.
Earlier this year, the First Minister said the Scottish Government would refresh the prospectus for an independent Scotland in a series of papers.
The details, Ms Sturgeon said on Friday, will be laid out in full when the paper is published, but she did reveal work on a Scottish central bank would begin immediately after a Yes vote, with the newly-independent country keeping the pound for "some time", as had previously been stated.
She told the Good Morning Scotland programme: "In terms of setting up a central bank, we would start that process as soon as Scotland voted for independence.
"That central bank would be the provider of advice to the Scottish Government on these matters, it would be the lender of last resort for our financial services industry, it would require reserves that could cover these limited functions in that first period.
"We have said, and this is my party's position, that we would move from using the pound, we would continue to use the pound after independence... and we would move to a Scottish pound when the economic conditions were right."
