Scottish First Minister Alex Salmond said on Monday he expected to meet Prime Minister David Cameron this week to discuss their differences over a referendum that could pave the way for Scotland to break away from the United Kingdom.

Salmond said he held a useful two-hour meeting with Scottish Secretary Michael Moore on Monday in Edinburgh but added that the real power resided with Cameron.

Some modest progress was made at this meeting, Salmond told reporters. There were certain areas on which there appeared to be agreement including the timing of a referendum, he added.

Moore himself played down talk of an agreement on when to hold the vote.

The British government, which opposes a breakaway, wants the vote to be held as soon as possible, whereas Scottish National Party (SNP) leader Salmond is preparing for a vote in the second half of 2014.

A delay would allow the SNP time to build support for independence and a vote in 2014 would also coincide with celebrations of the 700th anniversary of the Battle of Bannockburn, a historic Scottish victory over the English.

Salmond said he expected to meet Cameron in Edinburgh on Thursday in what would be their first substantive talks since Cameron called in January for an early referendum, saying uncertainty was harming Scotland.

The prime minister's office has not confirmed the meeting.

The SNP wants 16 and 17-year-olds to be able to vote in the referendum and would also like to offer Scots the option of voting for increased devolution, a third option in addition to the status quo or independence.

The government favours a simple yes or no question on independence alone.

(Reporting by Ian Mackenzie in Edinburgh; writing by Keith Weir in London)