Plans to trigger another referendum on independence have been announced by Scotland's First Minister Nicola Sturgeon.

Didn't Scots just have a referendum on independence in 2014?

Scots voted by 55% to 45% to stay part of the UK in September 2014. Despite that vote, the issue is far from resolved.

Following the referendum, the SNP saw a massive surge in membership, with the nationalists now the third biggest political party in the UK. More evidence of the party's popularity came in the 2015 general election when they won all but three of the 59 seats up for grabs north of the border.

In 2016 the party won a third term in power at Holyrood, although Nicola Sturgeon lost the overall majority her predecessor Alex Salmond had won in 2011.