Britain promised to guarantee Scotland high levels of state funding, granting Scots greater control over healthcare spending in a last-ditch attempt to shore up support for the United Kingdom before Thursday's vote on independence.
With polls showing the decision on the fate of the United Kingdom is too close to call, welfare spending and the future of the revered National Health System have formed a central part of nationalist Alex Salmond's case for secession.
In a deal brokered by former Labor Prime Minister Gordon Brown, the leaders of Britain's three main political parties said they would retain the funding equation that sustains a higher level of public spending north of the border.
People want to see change, said the agreement, published in Scotland's Daily Record newspaper and signed by Prime Minister David Cameron, Labour leader Ed Miliband and Liberal Democrat leader Nick Clegg.
A no vote will deliver faster, safer and better change than separation, the agreement said.
Cameron, whose job is on the line if Scots vote to break the United Kingdom, warned on his last visit to Scotland before Thursday's vote that there would be no going back and that any separation could be painful.
British leaders accept that even if Scotland votes to keep the 307-year union, the United Kingdom's structure will have to change as the rush to grant so many powers to Scotland will provoke calls for a less centralized state from voters in England, Wales and Northern Ireland.
Swathes of voters in the former industrial heartlands of northern England and Wales depend on state welfare spending while some English lawmakers in Cameron's own party have already asked for England to be given more powers.