Scottish first minister and SNP leader Nicola Sturgeon said this shortly before her party unveils its 2016 election manifesto on Wednesday 20th.
UK citizens are called to decide, on June 23th, whether they want their country to remain in the EU or leave it. The SNP said in recent months that a second independence referendum should be called if the UK voted to leave the EU while Scotland voted to remain.
Another scenario that could justify a second referendum, Sturgeon said, could be the emergence of "clear and sustained evidence" that Scots wished to move towards independence.
To the left of the SNP, anti-capitalist alliance RISE is also unveiling its manifesto these days. The alliance, which includes the Scottish Socialist Party (SSP), argues a second referendum should be called within the next 5 years, even if Westminster did not agree to that. The UK government has made it clear it does not want another independence vote since too little time has passed since the last one.
Meanwhile, the Greens' manifesto argues a second referendum should be called only if there was a popular demand for it. The Greens say a central task of the next parliamentary term will be to provide Scottish citizens with legal means through which they can take part in "open and participatory" decision-making processes -one of them that could lead, for instance, to a second referendum. In that event, the Greens say that they would again campaign for independence.
The Scottish independence referendum was held in September 2014. 55% of voters rejected breaking up from the UK. Over the campaign's last days, the leaders of the three major UK parties promised a substantial increase in Scotland's self-government if Scots voted against independence. The SNP believes that the promise has not been fulfilled since new agreed devolved areas do not meet the expectations of the people of Scotland.
According to opinion polls, the SNP will achieve an even wider victory than in 2011. This would certainly lead to a reinforced absolute majority for the pro-independence party in the Scottish Parliament.
Surveys say Labour -the main unionist party- will be losing some ground. The Greens and the Conservatives are expected to make gains. Eurosceptic and anti-devolution UKIP could gain some seats in the Scottish Parliament for the first time ever. On the contrary, it seems unlikely that RISE can have any of its candidates elected.