MPs have begun debating an order to allow Holyrood to hold a referendum on Scottish independence, which is expected in the autumn of 2014.
Scottish Secretary Michael Moore said formally passing the power to the Scottish Parliament would mark the end of discussions about process and allow the "great debate" to begin.
He told MPs on 15 January 2013 the measure would enable Holyrood to hold the legal, fair and decisive referendum pledged in the Edinburgh Agreement signed by David Cameron and Alex Salmond last year.
The deal sets out terms for a Scottish independence referendum after the SNP secured a mandate to hold a poll following its landslide Scottish election win in 2011.
Under the order, which changes the Scotland Act 1998, the Scottish Parliament will be allowed to agree issues including the franchise, question and campaign finance for the independence referendum.
Labour's Margaret Curran said the referendum should settle the issue of independence "decisively once and for all".
The shadow Scotland secretary reiterated Labour would make the argument for a "prosperous Scotland within the United Kingdom".
Liberal Democrat former leader Charles Kennedy accused Mr Salmond's SNP party of playing "somewhat fast and loose" with the facts during their campaigning for an independent Scotland, "which won't serve them or the process well".
He said the SNP should "create a degree of calm" by ruling out holding a further referendum if it is defeated in next year's vote.
Angus Robertson, the SNP's leader in Westminster, said devolving the power for the referendum was a "huge milestone".
He told MPs it "says much about the potential for further respect and equality between the governments, the parliaments and the peoples of these islands".
Challenged by Labour former chancellor Alistair Darling about the role of the Electoral Commission, Mr Robertson said its views would be listened to but refused to say that its advice would be followed.
Mr Darling told the Commons the Electoral Commission should act as "referee" in the vote.
"Whatever the result, we want to be able to be in a position where we accept Scotland had its say, Scotland reached its verdict and let us then abide by that," he added.
Conservative MP Rory Stewart said the debate on separation needed to be widened "far further" and for more money to be spent so that the subject to be discussed as openly as possible.
He said the media had failed to set out the opposing arguments "powerfully enough", for fear of being "too political" on one side or the other.
Later in the debate MPs agreed without a vote to hand the Scottish Parliament the powers it needs to hold the referendum on independence.