The Yes campaign fighting for Scottish independence is ahead for the first time, a poll has revealed.
A YouGov poll, undertaken for the Sunday Times, found 51 per cent supported independence, compared to 49 per cent who want to remain in the UK.
It is the latest example of a surge in support for independence, which has seen the gap between the sides vanish in months.
The poll suggests the Yes vote has increased by four points, as No dropped by the same number.
Scotland's Deputy First Minister Nicola Sturgeon described the poll as "exceptionally positive" but added that the Yes campaign "still has a lot of work to do to win".
Alistair Darling, leader of the pro-Union Better Together campaign, said the poll "must now serve as a wake-up call to anyone who thought the referendum result was a foregone conclusion".
The former Chancellor said: "The polls may conflict, but the message I take from them is clear: If you want Scotland to remain part of the UK family you have to vote for it on 18 September. Separation is forever.
"These polls can and must now serve as a wake-up call to anyone who thought the referendum result was a foregone conclusion. It never was. It will go down to the wire. Now is the time to speak up and speak out."
Rumours about the latest YouGov findings had been swirling for days. The firm has charted a remarkable turnaround for Yes, which has seen them recover from a 22 point deficit in just one month.
Writing in the Sunday Mirror, former prime minister Gordon Brown acknowledged that the referendum battle was proving tougher than some had expected - and laid the blame squarely with the Tories.
"Why has it been difficult to win Scottish votes in support of this principle of sharing that most Scots hold dear?" the Labour MP for Kirkcaldy and Cowdenbeath wrote.
"Many are angry that the Bedroom Tax was imposed upon Scots against their will while at the same time the very wealthy received tax cuts.
"The SNP also claim that the ramifications of any Tory privatisation of the NHS in England will cut budgets in Scotland.
"But English and Welsh people have already given an answer to the SNP claims.
"The answer is that 90% of English people want to keep the NHS public and retain it free at the point of need.
"And the vast majority across the whole UK dislike the Bedroom Tax and would even consider more taxes to make our NHS better."
