Ed Miliband has called on Scots to reject independence and join his “mission” to bring social and economic change to the UK.
The Labour leader said there was “deep discontent” across the country, with people “crying out” for economic change.
He said that “in the face of an economy that doesn’t work and a politics that is broken, some people might be tempted to vote Yes” to Scottish independence in September’s referendum
Mr Miliband insisted: “There is another, better way of changing things. Our mission - economic and social change.”
With less than three months to go until voters in Scotland decide the future of the UK, Mr Miliband told an audience in Edinburgh: “By saying No in the referendum, the people of Scotland can say Yes to the campaign to change Britain as a whole.
“To change our economy and the way we are governed.”
Labour has already pledged to deliver more devolution to Scotland - including new income tax powers - if the Scots opt to stay in the United Kingdom.
But he said that devolution “must not stop in Scotland”.
Mr Miliband said the Welsh Assembly should be put “on the same legal footing as the Scottish Parliament”.
He also said his party would set out its plans next week to “restore the great cities of our country as the great powerhouses of our economy”.
The Labour leader pledged: “We will be better able to change Scotland and the whole of the UK if we stay together.”