Scotland's three islands councils can look forward to receiving all the Crown Estate's income from the seabed round their shores, if there is a Yes vote in the independence referendum.

News that Orkney, Shetland and Western Isles stand to get 100 per cent of the rent from leases for the likes of cables, pipelines, fish farms, wave, wind and tidal devices, piers, local authority harbours and moorings, surprised many.

In the Scottish Government's "Scotland's Future guide to an independent Scotland", the proposal was more than 50 per cent of income.

It is among one on the new powers and rights unveiled by the First Minister yesterday to give island communities greater control over their local economies and natural environment while being represented at the heart of government in an independent Scotland.

Described by Angus Campbell Western Isles Council's leader as "a historic day for our island communities", it is widely seen as a mark of the success of the islands' campaign for more powers launched last year.

This was predicated on the belief that whichever way Scotland votes, more powers would be coming to Holyrood, so the islands should get more power as well.

The UK Government is expected to publish its plans soon for the islands in the event of a No vote.

Under the prospectus "Empowering Scotland's Island Communities" unveiled by Mr Salmond in Orkney, there would be an Islands Act. It would place a duty on the Scottish Government and other public bodies to 'island-proof' their functions and decisions, to ensure the facts of island life were recognised.

There would also be a Minister for Island Communities and a new Scottish energy regulator, which would ensure that the regulated energy market supports renewable energy generators on the islands and crucially "the development of the necessary island grid connections."

Mr Salmond said: "Today's prospectus is the most comprehensive package for empowering Scotland's island communities that has been put forward by any Government. It recognises the unique contribution that island communities make to modern Scotland."

Convener of Orkney Islands Council Steven Heddle the Scottish Government's document represented "a comprehensive commitment to islands in general."

But LibDem MSP Orkney Liam McArthur criticised the Scottish Government for not doing more for the isles with the powers it already has, accusing the SNP of "holding issues hostage" in the referendum run up.

A Crown Estate spokeswoman fsaid: "There were already ways in which authorities could control and manage the foreshore."