Labour Party leader Ed Miliband believes "the fight is now on" for the UK after the signing of the Scottish referendum deal.
The agreement between the UK Government and the Scottish Government on a referendum states:
– Agreement between the UK and Scottish Governments on a referendum on independence
The governments have agreed that the referendum should have a clear legal base; be legislated for by the Scottish Parliament; be conducted so as to command the confidence of parliaments, government and people; and deliver a fair test and decisive expression of the views of people in Scotland and a result that everyone will respect ...
The referendum legislation will set out the date of the referendum; the franchise; the wording of the question; rules on campaign financing; and other rules for the conduct of the referendum.
The Prime Minister has said he believes "passionately" that Scotland should stay in the United Kingdom, but he said he "believes in showing respect to the people of Scotland" by granting them a referendum.
The terms of the referendum agreed today state that "it will be for the Scottish Parliament to approve" the move to extend the vote to 16- and 17-year-olds.
The ruling SNP party favours a wider franchise because independence is more popular among the young.
ITV News' Scotland Correspondent Debi Edward spoke to some 14-year-olds about the prospect of being able to vote:
The Prime Minister and Scotland's First Minister have agreed on terms for a referendum on Scottish independence to be held in autumn 2014. You read the full text of the agreement here.
Scotland's First Minister Alex Salmond shook hands with the Prime Minister before their meeting on Scottish independence.
The pair sat opposite each other for the meeting, flanked y the Scottish Secretary and Deputy First Minister of Scotland.
On the wall behind Mr Salmond's back hung a picture showing the Scottish constituencies won by his SNP party at the last election.