On the question of whether Scotland should be an independent country, a new poll has found 52 per cent of Scots backed the idea, with 48 per cent voting no, of those who expressed a view yes or no.

In November the same question was Yes 54 per cent to No 46 per cent, meaning the eight point lead for Yes in the November poll has halved to four points in the latest results.

Looking at voting intention in the next Holyrood election, the pollsters said Nicola Sturgeon’s party retains a “commanding lead” over the other parties in the constituency section of the vote, although this dropped by 1 per cent from last month to 53 per cent.

The Tories and Labour are neck and neck on 20 per cent – with Labour up two points on November and the Conservatives up by one point.

The Liberal Democrats are on 6 per cent, with 1 per cent of respondents saying they will vote for another party.

In the regional section of the ballot, support for the SNP is 41 per cent, down one point from November.

Backing for Labour is up one point to 20 per cent, with support for the Tories increasing by the same amount to 18 per cent.

Meanwhile, 10 per cent said they will vote for the Greens on the regional ballot, 7 per cent back the Lib Dems, 1 per cent are in favour of both the Brexit Party and UKIP and less than 1 per cent support other parties.

Survation published the research after questioning 1,018 people aged 16 and over between December 4 and 9.

SNP depute leader Keith Brown said: “Once again, a poll shows that independence is becoming the settled will of the people of Scotland, now with 16 polls in a row showing majority support.

“An independence referendum will be the choice of the people of Scotland and they will make that decision at the ballot box in May, not Boris Johnson.”

Mr Brown added: “The SNP will take nothing for granted and continue to work hard to gain the trust of voters ahead of the Scottish election in 2021.

“However, these polls continue to show that the people of Scotland believe our best interests are served as an independent country.”

Scottish Greens co-leader Patrick Harvie said: “This is just the latest opinion poll which shows the Scottish Greens on course to elect a record number of MSPs in May.

“It’s clear that our constructive approach to opposition is appreciated by the public, who see our current group of MSPs punching well above their weight.”

He added: “Although encouraging, we’ll continue to work hard for every vote, taking nothing for granted.”