NICK Clegg has insisted more devolution to Scotland is now "inevitable" if there is a No vote in September's independence referendum.
The Liberal Democrat leader made clear this guarantee will be one of the prices for agreeing a future coalition government with the Conservatives or Labour in the event of another hung Westminster Parliament.
In a speech today in Scotland, the Deputy Prime Minister will also point to the prospect of new post-referendum negotiations to establish a consensus on the future shape of extra powers for Holyrood.
They would involve not only the three main pro-Union parties but also the SNP, if it were willing, as well as civic Scotland and the business community.
Last week during a two-day visit north of the Border David Cameron gave his strongest indication yet that if there were a No vote, the Scottish Parliament would get more powers.
He even suggested it would be "desirable" to legislate in the first year of the UK Parliament after the 2015 General Election. The Nationalists dismissed his remarks as empty rhetoric.
Yesterday, Mr Clegg said: "Further devolution to Scotland, in the event Scotland remains part of the family of nations that makes up the United Kingdom, is now inevitable.
"There is an emerging and hardening consensus across all the mainstream parties. My party has always advocated home rule; we've set out an ambitious programme of further devolution. Labour have now come up with their ideas, the Conservatives are about to publish their ideas.
"I certainly want the Liberal Democrats to act as the guarantor in any future government of further devolution to Scotland because that is the right future for Scotland in the UK."
Today in a speech to the Scottish Chambers of Commerce in Edinburgh, Mr Clegg will make similar points, stressing a No vote is not a vote for the status quo.
He will tell business leaders: "You should know - all of Scotland should know - that saying No to leaving the UK and the EU does not mean No to more change."
Mr Clegg will make clear that one of his party's proudest achievements was the 2012 Scotland Act giving Holyrood more powers on tax and borrowing, which he will stress was a key part of the 2010 Coalition negotiations with the Tories.
"More powers will come," the LibDem leader will insist. He noted that from 2016 the Scotland Act will mean Holyrood will raise 30% of income from tax but the LibDems want this to be more than 50%.
However, Mr Clegg will add the "settlement on further powers will need to be negotiated" between the three pro-UK parties, the SNP, if willing, and those outside politics.
Asked about the promise of more powers on the back of a No vote, Nicola Sturgeon dismissed the notion, saying: "I'm sceptical about whether the other parties will deliver that.
"That's one of the many reasons I'm campaigning for a Yes vote, because the only way to guarantee more powers for the Scottish Parliament is to vote Yes.
"We hear lots of vague words from the other parties on the No side but we don't hear anything very concrete.
"But I don't remember it very clearly because I was fairly young, Scotland was promised more powers if it voted No in the 1979 referendum and all we got was 18 years of a Tory government.
"I don't think we should take that risk again. We should guarantee more powers by voting Yes."