Separate legislation will be brought forward if there is a second vote on independence, the Scottish Government has announced.
Despite Holyrood approving the principles of legislation laying the framework for future referendums in Scotland, Michael Russell said a new short Bill would be introduced if there was to be indyref2.
The constitutional relations secretary also said he would hold talks with the Electoral Commission over whether or not the question used in the 2014 referendum could be used again, as the government wants.
But with the watchdog arguing it must be allowed to test the question again – a view backed by Holyrood’s finance and constitution committee – Russell would not commit to doing so.
He did accept questions would have a “shelf life” of how long they could be used for – suggesting this could be two Holyrood terms.
The Tories, Labour and Liberal Democrats all voted against the Referendums (Scotland) Bill, accusing SNP ministers of using the legislation to try to “rig” a future second independence referendum.
Russell insisted the Bill – which passed stage one by 65 votes to 55 – was about a seeking to “establish a high quality set of rules” in order to “ensure the conduct of future referendums is robust, transparent and in the interests of the voters”.
He announced the Bill will be amended to increase the maximum penalty that can be applied for any breaches of referendum rules – taking this from £10,000 to £500,000.
And the minister confirmed changes would be made so any future vote on constitutional issues would require the government to bring forward primary legislation.
Russell said: “I agree that normally a short Bill should be the way to trigger a referendum and for the avoidance of doubt I can confirm that any proposal for, for example, a Scottish independence referendum, should now require a short Bill.”
On the issue of the question, he said polling had shown 77% of Scots would be “satisfied” for the 2014 proposition – Should Scotland be an independent country? – to be asked again, with only 10% against this.
But he said he would discuss the issue with the Electoral Commission and would potentially make changes to the Bill as a result.
Scottish Conservative constitution spokesman Adam Tomkins said: “Not only are the SNP trying to steamroller us into a second independence referendum, they are trying to rig that referendum by playing fast and loose with its rules.
“This Bill is designed with only one purpose in mind, to pave the way for an unwanted second independence referendum.
“We will oppose the SNP’s attempts to steamroller Scotland into an unwanted second independence referendum every step of the way.
“For that reason we will oppose this unwanted Referendums Bill at every stage.”
Labour’s Alex Rowley said while ministers had portrayed the legislation as being “simply being an administrative procedure to facilitate future referendums”, it was in fact “the SNP indyref2 Bill”.
He added: “Rather than trying to rig a referendum, this government here in Edinburgh should bring a halt to this legislation and free up the time to allow this parliament to focus on the kind of transformation our country needs.”
Liberal Democrat Mike Rumbles said it was an “163-page Bill… the people of Scotland do not want”.
He added: “The Scottish Government have wasted a huge amount of time and resources in bringing this 163-page Bill forward.”
Scottish Greens co-leader Patrick Harvie, whose party backed the government, said while “clearly” changes were required to the Bill, Russell had “acknowledged that”.
Harvie said he “struggled to see why” Scottish ministers would not allow the Electoral Commission to test any referendum question.