THE SNP has claimed opposition attacks on independence are failing after a poll showed support for it has grown since the Holyrood election.

The poll, revealed in The Herald yesterday, showed the number of people who would back going it alone in a referendum has increased by six points to 37% since the last poll in November 2009.

It also showed 45% would vote no, one point down on the 2009 poll, and 18% of people did not know how they would vote, down five points from the last poll.

SNP campaign director Angus Robertson said the pattern showed the party's momentum continuing "as people across Scotland recognise the positive benefits of independence".

He added: "It shows the negative attacks rolled out by opposition parties on Scotland's abilities as an independent nation are failing once again."

However, a Labour spokesman insisted the poll showed "support for separation at among its lowest level in recent years and confirms the settled will of the Scottish people remains unchanged".

He added: "The number of Scots who believe Scotland benefits significantly from being part of a strong UK far outstrips those who want to see Scotland ripped off from the rest of the UK."

Scotland Office minister David Mundell said polls suggesting a rise in support for independence "don't necessarily reflect that people have fully thought through what independence would mean and would actually support that".

The Tory minister added: "Those supporting independence have to be honest about what it really means and we are now at that stage."

LibDem leader Willie Rennie said the SNP had "to come clean on the costs, the question and the consequences of independence".