THE SNP and Scottish Greens may not achieve a pro-independence majority at the 2021 Holyrood elections, according to a new opinion poll.

Such a result would scupper the chance of a second independence referendum during the next parliamentary term should Nicola Sturgeon not convince Boris Johnson or Jeremy Corbyn to allow a plebiscite next year.

The First Minister has said she wants to hold an independence referendum in the second half of next year, but both contenders for Number 10 have ruled out that request.

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Johnson’s Tories have signalled they would not back another independence referendum until the 2050s, while Corbyn has said it would not be a priority in “the early years” of a Labour Government suggesting he would allow one sometime after 2021 if there was a mandate for one in the Scottish Parliament elections.

The National: Jeremy Corbyn said an indyref would not happen in the early years of Labour ruleJeremy Corbyn said an indyref would not happen in the early years of Labour rule

However, the Panelbase poll of 1009 people for The Sunday Times yesterday shows this may not be achieved.

For the constituency vote, the poll — conducted on November 20-22 — puts the SNP on 43% (+1 since last month), with the Tories on 26% (+5%), Labour on 17% (-2) and Lib Dems on 9% (-1), with the Brexit Party on 3% (-1) and the Greens on 2% (-1).

For the regional vote the SNP are on 39% (+1), the Tories 25% (+4), Labour 17% (-1), LibDems 9% (-2), Greens 6% (unchanged) and Brexit Party 3% (-1).

John Curtice, professor of politics at Strathclyde University, calculates that on this showing — assuming a uniform swing — the SNP would win 60 seats and the Greens four, leaving them one short of a majority.

Among the unionist parties, the Tories would win 35 seats, Labour 21 and the LibDems nine, enabling them to vote down a referendum.

With a hung parliament a strong possibility after polling day on December 12 Sturgeon has demanded that her price for supporting a minority Labour Government would be an independence referendum next year.

This also throws up another challenge to Scottish Labour MSPs by revealing that they risk being out of step with their own supporters if they block another independence referendum.

Panelbase found that only 45% of Labour supporters believe there should not be another independence referendum in the next few years. One-third (33%) favour one once the UK has finished negotiating to leave the EU while 22% want one without delay while those negotiations continue.

In addition almost half (49%) of Labour voters now back Scotland becoming independent — while across all voters opposition to independence leads by 51% to 49%.

Panelbase found that across adults in Scotland as a whole, 27% believe another independence referendum should be held while the UK is negotiating Brexit — (+8 since last month) while 25% (-6) say it should happen when the UK has finished negotiating to leave the EU. Some 48% (-2) say there should not be another Scottish independence referendum in the next few years.

One note of caution is that the Scottish Greens have had a low profile during this UK general campaign and would hope to gain ground during a Holyrood campaign.

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Panelbase interviewed 1009 adults in Scotland on November 20-22.

Meanwhile, in a sign the election campaign could go down to the wire, across the UK Labour has cut the Tory lead to nine points, a narrowing of two percentage points since YouGov’s last survey on Wednesday.

In the latest YouGov poll for The Sunday Times, the Tories are on 43% with Labour up two to 34%, the LibDems static on 13% and the Brexit Party down to just 2%.

It is still enough for a Conservative majority, but if Labour gains two more points it will be touch and go.

The FM has made it clear she will write to whoever is Prime Minister by Christmas to request the transfer of necessary powers under Section 30 of the Scotland Act 1998 to Holyrood to hold a new independence referendum next year.