David Cameron is prepared to let Alex Salmond select the timing of the Scottish referendum and the wording of the question provided voters are offered a straight "yes or no" choice, it emerged yesterday.
Aides say the Prime Minister is also willing to allow 16 and 17 year olds to cast their vote in the poll – a key demand of the Scottish Nationalist Party because young people are considered more likely to back independence.
But one issue on which Mr Cameron is not prepared to budge is the number of options that would be put to the Scottish electorate.
SNP officials are thought to be keen on offering voters a third "devo-max" option which would allow them to express a preference for the Scottish Parliament to be given more powers short of full independence.
But Mr Cameron, buoyed by new research showing a fall in support in Scotland for independence following the success of Team GB at the Olympic Games, is adamant that voters should be presented with a straight "in or out of the Union" choice, arguing that any decision to increase the authority of the Holyrood parliament can be enacted by legislation in the Commons without a referendum.
A weekend poll of Scottish voters suggests that over the Olympic period opinion shifted in favour of staying within the United Kingdom,
The sample of 1,177 adults question by YouGov, for the Scottish Mail on Sunday, produced a majority of 60 per cent opposed to Scotland becoming an independent country, with 27 per cent in favour and 13 undecided.
The poll also showed nearly two thirds of 18 to 24 year old opposed to separation from the rest of the UK. This contrasts with a YouGov poll taken at the end of last month when 54 per cent were opposed to independence, 30 per cent were in favour, and 16 undecided.
Last week the Scottish minister David Mundell and the SNP's Bruce Crawford thrashed out a timetable to get the necessary legislation through by February to make it possible to hold the referendum in the first half of next year.
The Scottish First Secretary Alex Salmond and the Scottish Secretary Michael Moore are due to begin talks on the other details in September.
"The timing is not a barrier to negotiation, though we think the sooner the better, and we're prepared to have discussion about the wording and the voting age. We want a decision on these things by October," a Downing Street spokesman said yesterday.
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