Douglas Ross's Scottish Conservatives could be pivotal in forming the next Scottish Government, Professor Sir John Curtice has said. 

The academic was speaking as a new poll showed the gap between Labour and the SNP narrowing significantly. 

Survation found that on the Holyrood list vote, both parties were set to win 30%. The Tories were on 15%, and both the Lib Dems and Scottish Greens on 9%.

On the Scottish Parliament constituency vote, the SNP were at 39%, while Labour was on 34%. The Tories were on 16% and the Lib Dems on 8%.

READ MORE: Poll shows Labour could pick up 24 seats, says Curtice

According to Prof Curtice, if this was reflected at the next Scottish Parliament election — not expected until 2026 — this would give the SNP 49 MSPs, Labour 42, the Tories 17, the Lib Dems 11 and the Greens 10.

That would mean that neither the SNP and Greens, nor Labour and the Lib Dems would have enough MSPs for a majority at Holyrood.

"Which of course does mean that the Conservatives are potentially the kingmakers," Professor Curtice told an online briefing organised by True North, the political consultancy that commissioned the poll.

"A role, of course that de facto, they were able to perform in the 2007 to 2011 Holyrood parliament.

"Now a dim and distant memory because the polarisation of Scottish politics is such that nobody could ever possibly now conceive of a Conservative parliamentary party at Holyrood being willing to help to prop up a minority SNP administration, but that's effectively what happened."

The Herald:

Prof Curtice said it be "very difficult to believe" that a Labour minority administration would also be keen on being beholden to the Tories. 

"If Labour have taken any message from the 2014 independence referendum it is thou does not sup with the devil of the Conservative Party, at least not in open."

READ MORE: Nicola Sturgeon: Police security detail 'withdrawn from former FM'

"Which does therefore effectively raise a question.

"Now of course, it's a long way not to the next Holyrood election, but that unless the SNP do recover or unless Labour makes much further progress than they have done so far, we do potentially face a situation at Holyrood in 2026 where it's going to be very difficult for anybody to run any kind of stable administration."