The First Minister is "happy" to open discussions with the Prime Minister about the timing of a second independence referendum.

Nicola Sturgeon will offer Downing Street the chance to start talks about a fresh independence vote in her speech at the SNP conference later on Saturday.

On Monday, Sturgeon said she wanted a referendum to take place between autumn next year and spring 2019.

This was ruled out by the Prime Minister and the Scottish secretary, David Mundell, on Thursday.

Next week the Scottish Government will ask the Scottish Parliament, which has a pro-independence majority of SNP and Green MSPs, to authorise the First Minister to request a section 30 order from Downing Street - the legal instrument to hold an authorised referendum.

Mundell warned the First Minister that "any request" for a section 30 order "will be declined" by the UK Government.

The UK Government has said it will not enter into any discussions about a referendum until the UK has formally left the EU, an event which is not expected to take place until March 2019 at the earliest.

Talks over the first Scottish independence referendum lasted from January 2012, when then-prime minister David Cameron signalled his openness to one, until the Edinburgh Agreement was signed in October of that year.

The section 30 order to organise the 2014 poll was not then granted for a further four months.

In an interview with STV News on Friday, the SNP leader refused to rule out holding an unauthorised referendum if Downing Street does not change its position.

The SNP leader will tell conference delegates: "If a majority in the Scottish Parliament endorses that position, the Prime Minister should be clear about this.

"At that point a fair, legal, agreed referendum - on a timescale that will allow the people of Scotland an informed choice - ceases to be just my proposal, or that of the SNP.

"It becomes the will of the democratically elected parliament of Scotland."

She will add: "To stand in defiance of it would be for the Prime Minister to shatter beyond repair any notion of the UK as a respectful partnership of equals.

"She has time to think again and I hope she does. If her concern is timing then - within reason - I am happy to have that discussion.

"But she should be in no doubt: The will of our parliament must and will prevail."

The First Minister will also use her conference address to announce a new £36m fund to improve digital skills among Scotland's workers.

Loans will be provided to firms by the Scottish Government to improve cybersecurity, data analysis and software engineering.

The SNP leader will say the fund "will see up to 6000 people per year able to access the training" and will "lift the upfront burden of up skilling Scotland's workforce".

Scottish Conservative chief whip John Lamont commented: "Nicola Sturgeon said as late as Thursday that a referendum after April 2019 would be 'too late'.

"Now she has changed her mind and appears to be trying to engage in some kind of horse-trading with the UK Government.

"The future of Scotland is not a game. It is time for the First Minister to act responsibly over our future."