THE SNP yesterday claimed Scotland could be a non-nuclear state without quitting Nato, attacking the view of former Nato chief Lord Robertson that this would not be allowed.

While playing down claims of an imminent policy shift, senior SNP figures insisted that there would be nothing inconsistent about an independent Scotland continuing to renounce nuclear weapons and opting to stay in Nato.

Lord Robertson of Port Ellen had claimed all Nato members must sign up to the alliance's Strategic Concept policy confirming that they remain part of "a nuclear alliance".

But the SNP dismissed this as "a nonsense", citing the words of the Norwegian defence minister Johan Holst almost a quarter of a century ago on his country's stance as evidence that non-nuclear ambitions could co-exist with Nato membership.

This stated: "Norway will not test, produce, or in any other way attain, nuclear weapons; nuclear weapons will not be stored in or deployed to Norway; Norwegian armed forces will not be trained in the use of nuclear weapons.

"Norway will not enter into any co-operation agreement with an aim to transfer nuclear weapons or information about nuclear weapons to Norway; special storage sites for nuclear weapons will not be established in Norway; Norwegian weapon systems will not be certified for use of nuclear munitions."

In spite of this unequivocal anti-nuclear stance, Norway remains a full member of Nato.

Labour's Shadow Scottish Secretary Margaret Curran accused the SNP of being in a state of chaos over its policy. "The SNP cannot even tell us whether their policy of withdrawal is up for discussion or not. There is clearly confusion and no leadership on this issue at all," she said. "The days of Cold War politics are over, and those that think that is what Nato is all about are profoundly mistaken. Partnership and alliances are critical for trade, security, intelligence and co-operation."

The SNP pointed out that no motions have yet been tabled ahead of June's decision-making body, the National Council, so talk of a major policy debate on the issue of Nato membership was premature.

But it is clear a shift in ground is being prepared, and one backbencher told The Herald that provided there was no shift in the party's anti-nuclear stance there was not likely to be a major divide over the Nato issue.

"The world has moved on in the last decade and so has the debate, just so long as there is no sign that this would impact on the non-nuclear policy. That is a touchstone," the MSP said.