A FUTURE pro-independence campaign will lose a second referendum if voters believe they will be poorer as a result of Scotland quitting the UK, the SNP's Westminster leader has said.

Angus Robertson, seen as the frontrunner in the race to succeed Stewart Hosie as deputy leader, won agreement from his fellow candidates when he pinpointed currency and pensions as the two key areas that need to be re-examined ahead of a repeat referendum which Nicola Sturgeon has said is "highly likely".

He made the comments to SNP activists as he squared off against MP Tommy Sheppard, MEP Alyn Smith and councillor Chris McEleny in a good-natured hustings event in Dunfermline.

Mr Robertson, asked by an SNP member for two changes to economic policy that would win over No voters ahead of a future referendum, warned that a Yes campaign would fail if it spoke only to those who already backed independence.

He said: "The two things in relation to the economy that are absolutely key are the currency and our pension offer. There are two economic related issues I think all of us would recognise from the referendum campaign where we did not persuade enough people - it is those two issues.

"One thing we need to be very mindful of, is that when we come to how we best protect Scotland's place in Europe, when the First Minister's process of consultation is over, I think we need to be absolutely clear that we cannot refight the 2014 Scottish independence referendum campaign.

"That means we have work to do. Work to do on currency, on pensions, work to do on the rest of our offer. We should not lose sight of this - we are not going to get the ball over the line by just appealing to the 45 per cent. So, who among the 55 per cent do we need to convince? A lot of those are people who feared they were going to lose. They were going to lose personally, their families would lose out, there would be economic uncertainty to them.

"Unless we have them in the forefront of our minds, we are going to have the same result again. We need to get currency right and we need to get pensions right."

Mr Sheppard, a comedy club boss and Edinburgh MP who only joined the SNP in 2014, agreed that currency was a key issue, saying it "needs to be looked at anyway" as the prospect of Scotland being an "independent European nation" within the EU while England is not changed the argument from 2014. He called for the establishment of a Scottish central bank to be considered.

He also suggested that the SNP could propose a state-owned renewable energy company in a bid to make Scotland the "renewables capital of Europe" within a generation.

However, he warned against tying a future Yes campaign too closely continued membership of the EU. He said: "Once we decide to become an independent country, then we have the power, and responsibility, to make any changes we want and I would certainly argue we should play an active part in the European Union and be an independent European country but others will disagree. The question is simple: whose decision should it be whether Scotland is a EU member or not? Should it be the people of Scotland, or should it be the people that live in a different country?"

Mr McEleny won loud applause when he said SNP branch meetings were "boring" and that far more time should be devoted to discussing politics and policy.

He added: "Most people now accept we lost the last referendum because of the economy, and because a certain demographic of people thought their pensions weren't safe. That argument is changing, and so is the argument on currency. Many people will have gone on holiday this year and seen just how little you get for your pound compared with 2014."

To further applause, he added: "We are promoting an argument that we live in one of the wealthiest countries in the world. Why can we not have our own independent Scottish currency?"

Mr Smith, the long-serving MEP, agreed that currency and pensions were the two crucial areas but that the whole case put forward two years ago had to be looked at again.

He said: "We lost, I don't think we can be precious about what worked and what didn't, we didn't win. The proposition we will put forward, if and when we got to a point that there's a sufficient consensus that we can put one forward, will be a different proposition for a different world."