A new poll once again suggests Brexit may doom the British union - but also that staying in the EU might save it.

Fully 51% of Scots would support independence if Boris Johnson secures the working majority he needs to force through his leave deal.

But a Panelbase survey for the Sunday Times found the Yes vote would slump top just 42% if the Tory leader fails to deliver on his pledge to "get Brexit done".

The poll currently puts Yes on 47% and No on 53%, well within the range seen across recent surveys.

READ MORE: Support for Scottish independence has fallen, according to new poll

Polling expert John Curtice, speaking to the Sunday Times, said: “Getting Brexit done may end one constitutional argument — only to reopen another.”

The SNP, meantime, remains on track to pick up the most seats in this week's general election. Panelbase puts the party of Nicola Sturgeon on 39% and the Tories on 29%, with Labour and Lib Dems on 21% and 10% respectively.

Prof Curtice, of Strathclyde University, suggested this could result in the SNP gaining five seats to take 41 of a possible 56.

However, the Conservatives would hold on to all but one of their crucial 13 seats north of the border. A dozen Tory MPs from Scotland could prove key to Mr Johnson staying in Downing Street.

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The poll meanwhile suggested the Labour vote was particularly soft. Some 30% of respondents who are minded to vote for Jeremy Corbyn's party say they may change their mind. That is only true of 10% of SNP-minded voters, and 12% of Tories.

Local issues may mean Labour, however, holds on to two seats. Ian Murray in Edinburgh South and Lesley Laird in Cowdenbeath and Kirkcaldy, where her challenger has been suspended by the SNP over allegedly anti-semitic tweets.