The SNP have retained a commanding lead in the polls since the Scottish Parliament elections in May, according to a new survey.

The BMG poll of 1,010 Scots aged 16+ put constituency support for the nationalists in a Holyrood election on 40 per cent, the Conservatives on 16 per cent, Labour on 14 per cent and the Liberal Democrats on 6 per cent.

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When undecided voters are excluded, the SNP is on 51 per cent, the Conservatives on 21 per cent, Labour 18 per cent, Lib Dems on 7 per cent and other parties on 3 per cent.

For a general election vote the SNP is on 40 per cent, followed by the Tories on 16 per cent, Labour on 14 per cent, the Lib Dems 6 per cent and the Greens on 3 per cent.

Excluding those who are undecided, 49 per cent would support the nationalists, 20 per cent back the Tories, and 17 per cent would vote for Labour, with the Lib Dems on 8 per cent, Scottish Greens on 3 per cent and UKIP on 2 perf cent.

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First Minister and SNP leader Nicola Sturgeon remains the most popular leader in Scotland, with an approval rating of +16, closely followed by Scottish Conservative leader Ruth Davidson on +14.

According to the poll, carried out online between September 28 and October 4, Greens co-convener Patrick Harvie has a +10 approval rating, while Scottish Labour leader Kezia Dugdale is on -10 and Scottish Liberal Democrat leader Willie Rennie is on -3.

SNP business convener Derek Mackay said: "This is another remarkable poll showing strong support for the SNP after nine years in government.

"The public are firmly behind Nicola Sturgeon as she leads the Scottish Government's efforts to protect Scotland's place in Europe, and to protect Scotland from a hard-right Tory Brexit.

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"While Labour and the Tories turn in on themselves at the expense of the country, and Theresa May is still lacking any clear or coherent plan for leaving the European Union, it is only the SNP who have provided leadership in these uncertain times.

"While we take absolutely nothing for granted, this polling shows voters have confidence in the leadership shown by Nicola Sturgeon and the wider party."