The debate about Scotland's constitutional future must be a positive one, Deputy First Minister Nicola Sturgeon said.
Ms Sturgeon spoke out as she confirmed a referendum Bill would be introduced to Holyrood early in 2013, along with legislation to allow 16 and 17-year-olds to take part in the crucial ballot.
With the vote to determine whether or not Scotland will remain in the UK due to take place in 2014, she urged campaigners on both sides to ensure the debate takes place "in a positive way that encourages the people of Scotland to turn out and make an informed choice on their future".
She made the plea as former chancellor Alistair Darling, who is spearheading the campaign to keep Scotland in the UK, claimed the Nationalists had been "exposed as ill-prepared for this historic debate" and had "not thought through their answers to the really big questions".
Mr Darling, who is heading the Better Together campaign, said those who raised questions about the impact of independence were too often "accused of being negative or scaremongering".
He said 2013 would be "the year where we debate whether the people of the UK are to stick together or whether we are going to break apart".
And he argued: "We need a debate which is conducted in an atmosphere of respect on all sides."
The two rival politicians spoke at the end of a year in which Ms Sturgeon said a lot had been achieved to "ensure that Scotland can hold a referendum made in Scotland that is beyond effective legal challenge".
First Minister Alex Salmond launched the Scottish Government's consultation on the referendum in January.
In October, after months of negotiations between Holyrood and Westminster, Prime Minister David Cameron and Mr Salmond signed a deal on the staging of the vote.
Ms Sturgeon said that the Edinburgh Agreement would "ensure that the biggest decision the people of our country will make for many generations is made here in Scotland for the benefit of all of those who live and work here".
Although the referendum is not due to take place till autumn 2014, she said the debate about the country's future "has already begun in earnest".
She added: "Now that the legal basis of the referendum has been confirmed through the historic Edinburgh Agreement, the debate that follows on the substance of the argument must be a positive one - the people of Scotland deserve no less.
"I want to see - on both sides of the debate, and whatever we think Scotland's constitutional future should be - everyone involved engaging in a positive way that encourages the people of Scotland to turn out and make an informed choice on their future.
"The debate we will have over the next two years must be about how we can achieve the economic growth and social justice that the Scottish people would like in their country. I believe only the powers we will get through independence offer us the tools we need to build the country we want."
The Deputy First Minister also confirmed: "Early in the new year, I will introduce legislation for consideration by the Scottish Parliament, both on the main referendum bill that will set out how Scotland's referendum will be run, as well as the bill that will allow the Parliament to extend the vote to all 16 and 17-year-olds in Scotland.
"The Edinburgh Agreement means this will truly be a referendum designed and delivered by the Scottish Parliament." In his New Year message Mr Darling pledged to "continue to make the case that we are better together in the UK".
The Labour MP said: "This will be a choice between continuing the success of devolution within the UK and the risk of breaking away from Britain.
"It is a choice between concentrating on getting our economy back on track or years more instability and uncertainty as we turn our backs on our biggest market and closest allies. It will also be a choice between the values of unity and division."
He said a question as "important and irreversible" as Scotland's constitutional future "needs a full and detailed debate".
Mr Darling continued: "We need a debate which is conducted in an atmosphere of respect on all sides. Too often those who raise questions, without even taking sides on independence, are accused of being negative or scaremongering, when all they want to know are the answers to pretty basic questions."
He said: "We will be making the positive case that, on our small island, we have more in common than divides us, that Scotland has more to gain by working together with the rest of the UK family than by turning against each other, that our best future remains together rather than apart."
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