DAVID Cameron and his Government are doing all they can to create the circumstances for a second independence referendum, a leading SNP MP has claimed.

After the Prime Minister suggested that he was not minded to facilitate another poll given Nicola Sturgeon and other leading Nationalists had said last year’s referendum was a “once in a generation” event, Pete Wishart, the SNP's Shadow Commons Leader, hit back.

He said: “There will be a second referendum but the process of getting there is still uncertain.”

The MP for Perth and North Perthshire went on: “But the Westminster Government is doing all it can to stoke up that process in what it actually says; treating Scottish MPs like second-class citizens and not responding to the Scottish Parliament on more powers. If anyone is creating circumstances for a second referendum, it is the UK Government.”

There is a growing expectation that the First Minister will, at the SNP’s October conference, confirm that she will include in the party’s 2016 Holyrood manifesto the option of calling a second referendum before 2021.

For this to happen, two things will have to take place; Ms Sturgeon will have to determine a “material change” on a particular issue has happened and, as a result, the groundswell of Scottish public opinion is such that a second poll has to be called on Scotland’s future.

At the weekend, Alex Salmond, her predecessor, declared that another referendum was “inevitable” and that three things were moving things towards it: the failure by the Prime Minister to deliver fully on the Vow of more powers for Holyrood; the possibility of Scotland voting to stay in the EU and England voting to pull out and Chancellor George Osborne's continuing austerity agenda.

Some also believe that another policy could be the trigger: the renewal of Trident, the main decision on which is due early next year ie in the run-up to the Holyrood poll.

However, given Westminster remains the constitutional authority, it will be up to Mr Cameron to determine whether or not to sanction a second legal poll if Ms Sturgeon, on the back of a mandate next May, calls for one.

Last week, David Mundell, referring to the SNP’s 2016 manifesto, told The Herald: "Using a wording that allows maximum flexibility would hardly be capable of being held out as a mandate for a second referendum. If you want a second referendum, be upfront and be honest with the people of Scotland that that is your priority ahead of how much tax they pay, what welfare benefits they get, what happens in our schools or hospitals. It's time to be honest about it.”

On his South Asia trade trip, the PM stressed the lawfulness of any second poll, saying: “It is important that a referendum is legal and fair and properly constituted and that's what we had and it was decisive. So I don't see the need for another one."

Later, No 10 made clear Mr Cameron believed the issue of Scottish independence had been “settled for a generation”.