Scottish voters would vote for independence from the ­United Kingdom, according to a poll by Michael Ashcroft, the first ­major published survey to show a lead for independence since March 2017.

Asked how they would vote in an independence referendum, 46 percent of the 1,019 surveyed voters said they would vote for independence and 43 percent against. Excluding those who said they did not know or would not vote, this amounted to a lead of 4 percentage points for an independent Scotland.

"In the wake of [Prime Minister] Boris Johnson's visit to ­Edinburgh last week I polled Scots to measure support for a second independence ­referendum and to gauge opinion on independence itself," said Ashcroft, a Conservative who opposed Johnson's leadership.

"I found a small majority in favor of a new vote - and the first lead for an independent Scotland for more than two years." 

Scots rejected independence by 55 to 45 percent in a 2014 referendum but differences over Brexit have strained relations with the government in London.

The 52-48 vote to leave the EU in a 2016 referendum strained ties between the constituent parts of the UK: While Wales and England voted to leave, Scotland and Northern Ireland voted to stay.

The Scottish National Party, which runs the devolved government in Edinburgh and is the second-largest political party by membership in the UK, says that a second independence referendum is justified as Scotland is now being dragged out of the bloc against its will.