THERESA May has snubbed Nicola Sturgeon by not formally replying to the First Minister’s famous letter, which called on the UK Government to facilitate a second independence referendum.

Ms Sturgeon was memorably photographed sitting on a sofa in the drawing room of her official residence at Bute House, shoes off in a relaxed pose, while penning the letter, which drew parallels to a similar picture of Margaret Thatcher from 1983.

The FM wrote the letter in March to formally request that the Prime Minister enable the SNP administration, through a so-called Section 30 order, to hold a second poll on Scotland’s future.

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But The Herald has been told by senior Whitehall insiders that Mrs May never formally responded to Ms Sturgeon’s letter, which followed a vote in the Scottish Parliament. This requested the FM seek the power from Westminster – which is the UK’s constitutional authority on referendums – to hold a second independence poll.

At the time, Ms Sturgeon said the Scottish Government had mandate to seek discussions with the UK Government over a second independence poll and would seek “sensible and constructive discussion” with London.

“This is simply about giving the people in Scotland a choice. We agree that now is not the right time for that choice. But that choice should be available to the people of Scotland when the terms of Brexit are clear. So, I look forward to discussion in the weeks ahead,” added the FM.

In response, Mrs May made clear now was “not the time” for another poll and the Tory General Election manifesto pointed to how the UK Government would watch how Brexit panned out first before it would consider giving its consent to the Scottish Government holding another referendum on independence.

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This was widely seen as a clear signal that the PM had no intention of agreeing to another vote this side of the 2022 General Election. Indeed, during this week’s Conservative Party conference, she made clear that the issue of Scottish independence “has gone away”.

Last night, Pete Wishart, the SNP’s Shadow Commons Leader, said about Mrs May’s failure to reply to Ms Sturgeon’s letter: “If this is true, it would be truly astonishing as it is only courtesy and good grace to respond to the First Minister.

“It simply confirms the contempt shown by Whitehall towards the Scottish Government on constitutional issues. The UK Government really needs to get its act together and respond to such an important issue in a timely fashion.”

The Scottish Government was asked for a comment but declined to give one.