A prominent SNP politician calling for his party to draw up an alternative route to independence has called on colleagues to “seize the initiative” and not rule out May’s election being a “defacto referendum”.

The Scottish Government’s Constitution Secretary, Mike Russell, unveiled the SNP’s plans to hold a second referendum if Holyrood returns a pro-independence majority at May’s election.

Mr Russell set out the plans at a meeting of the SNP’s national assembly today – stressing that if a call was again ignored by Westminster, legislation would be drawn up at Holyrood for a vote to still be held, assuming Holyrood had a pro-independence majority after the election.

But Chris McEleny, who has consistnetly called on the party to draw up a Plan B , with Boris Johnson repeatedly stressing he will not cave to calls for a re-run of the 2014 referendum, has said that the SNP must set Boris Johnson a deadline of before the election to agree to a referendum so that “another mandate is not wasted “.

Mr McEleny wants the Scottish Government to set the UK Government a deadline to agree to a Section 30 order - the process to agree a referendum- of March 31.

READ MORE: Nicola Sturgeon says SNP's priority is 'legal independence referendum'

If the UK Government does not agree to a referendum, then Mr McEleny has argued it must not be ruled out that this May’s election is in itself turned into a referendum on Scottish independence, with a pro-independence majority being seen as a mandate to begin the process of Scotland leaving the United Kingdom. 

Mr McEleny believes his party is not being bold enough and is still giving Boris Johnson too much opportunity to stop any campaign for independence.

He said: “It is welcome that the party has finally conceded that the strategy of relying on Boris Johnson’s permission to hold an independence referendum was not going to work.

“The Scottish Government must progress with a referendum bill now, setting Boris Johnson a deadline to agree to a section 30 order before the election. Why wait until after the election to ask his permission, again, when we already have several mandates to hold an independence referendum, and we know he will say no?”

READ MORE: Analysis: Sturgeon ups political ante with Plan B: Holyrood staging its own Indyref2

He added: “A parliamentary majority exists now that can pass a bill, so that the necessary arrangements for a referendum can be made and implemented.

“In order that the outcome of this year’s election allows the case for Scottish independence to be progressed, as opposed to another mandate being stored in the trophy cabinet at the party’s HQ, we must now seize the initiative.

“The opportunity to turn May’s election into a de-facto referendum must not be squandered, or ruled out, especially if it may be the only opportunity to test the independence question for many years to come.”