BORIS Johnson will respond “in due course” to Nicola Sturgeon’s letter requesting the transfer of power to Holyrood to hold a second independence referendum, Downing Street has said.

The First Minister wrote to the Prime Minister on December 19, seeking the authority for Scotland to hold a new vote that would be “beyond legal challenge”.

She also published a 38-page document entitled Scotland’s Right to Choose: Putting Scotland’s Future in Scotland’s Hands, setting out the Scottish Government’s case for the transfer of power from Westminster to Holyrood. She also sent a copy to Johnson.

Ahead of MPs gathering for the first time today following the Christmas recess, a spokeswoman for the Prime Minister told The National he would reply to the First Minister’s letter.

She said: “We received the letter and the Prime Minister will respond in due course.”

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She declined to say whether the Prime Minister had read the letter, nor did she give any time frame about when the response would be made.

Writing to Johnson a week after the General Election, Sturgeon noted she had spoken to him the day after polling day and had told him then that she would be making the Section 30 order request.

She also noted that during their conversation he had re-iterated the UK Government’s position – which is to oppose a second independence referendum – but that he would “engage seriously” with the Scottish Government’s proposals.

The National:

“When we spoke on Friday, you reiterated your government’s position on this issue – however, you also committed to engaging seriously with our proposals,” Sturgeon wrote in the

letter last month. “Indeed, I believe that on this – as on any issue – you have a duty to do so in a considered and reasonable manner.”

“I therefore look forward to discussing matters further with you in the new year.”

In a new twist, the Scottish Government called in the document for Holyrood to be given the permanent powers to hold referendums on independence from the UK.

The move was in contrast to the process ahead of the 2014 vote which transferred independence referendum powers to Holyrood but on only a temporary basis.

Unveiling the document, the First Minister described the SNP’s success in the General Election as an “unarguable mandate by any normal standard of democracy” for a second independence vote.

The document also set out draft amendments to the statute which would devolve the right to hold votes on leaving the UK to Holyrood.

It also argued that there has been a “material change of circumstance” since the 2014 independence referendum, based on “the prospect of Scotland leaving the EU against its will and what the EU exit has revealed about Scotland’s position within the UK”.

Launching the document at an event at her official residence of Bute House in Edinburgh, Sturgeon said she “fully expected to get a flat no” from Westminster initially.

“I’m going to stand my ground,” she added.

“I fully expect today we will get the flat no of Westminster opposition, but that will not be the end of the matter and Boris Johnson should not be under any illusion that it is.”

Johnson used the Queen’s Speech following the General Election to argue that in his view a second independence referendum in 2020 would be a “damaging distraction”.