A SENIOR SNP minister has repeatedly insisted the wording of a future independence referendum should not be re-examined, despite a voting watchdog saying otherwise.

Constitutional Relations Secretary Mike Russell said 2014's Yes/No question had already been tested and was still in use in opinion polls.

He argued changing it would muddy the waters and confuse voters.

It comes after the Electoral Commission said it must be allowed to test any question ahead of a second independence poll.

The watchdog approved the question “Should Scotland be an independent country?” five years ago, but ruled against using a similar format for the 2016 EU referendum, favouring a Leave/Remain choice.

However, Mr Russell has repeatedly argued against this.

He told Holyrood’s Finance and Constitution Committee: “I’m not against testing questions.

“In fact, I believe in testing questions. What I’m against is retesting if circumstances do not require it.”

He added: “That question was used in 2014, and it has been used in opinion polls something like 56 times since then.

“It is, in our view, a question in current use. It is a question that met the criteria.

“So it has been tested. So any allegation that we do not, that I do not want testing, simply isn’t true.”

Mr Russell said he was in favour of testing but "not in favour of confusing people".

He said: "And if a question has been used again and again and again, and continues in use, then I think it would be a very serious step if you were trying to throw it out."

He added: "Far from saying that this would lack confidence, I think those who are challenging this question are, in some circumstances, attempting to muddy the waters because this question is clear, it has passed the test."

Mr Russell was giving evidence on the Referendums (Scotland) Bill, which seeks to draw up a framework for any future referendums.

The SNP still campaigns for a Yes vote, which would make any change to a Leave/Remain format difficult for the party.

Dame Sue Bruce, Electoral Commissioner for Scotland, previously said: "We strongly believe that the commission should be asked to test the question."

Pamela Nash, chief executive of Scotland in Union, said: “This Referendums Bill is a waste of precious parliamentary time, and MSPs should be able to focus instead on improving public services.

“Barely a quarter of people in Scotland support the SNP’s plans for a divisive second independence referendum before 2021.

“But if there ever is to be another unwanted referendum, the SNP must stop trying to rig it.

“Mike Russell’s comments are in direct opposition to what is being said by the independent Electoral Commission.

“The last thing Scotland needs is another referendum, but if it were to happen it must be fair and beyond reproach.

“This cannot be achieved without the involvement of the Electoral Commission in writing the question.”