Scotland is stepping gingerly toward another referendum on independence from the U.K., less than three years after Scots said ‘No’ to separation.

The country’s first minister, Nicola Sturgeon, confirmed on Monday that she will seek permission from the British government to hold another vote on the issue, which she would like to be held between the fall of 2018 and the spring of 2019.

Scottish voters rejected independence by 55% to 45% in the referendum in September 2014. What has changed since is the U.K.’s decision last year to leave the European Union, which most Scots did not agree with. Scotland voted by 62% to 38% to remain in the E.U.

However, it is far from certain that Scotland would vote for independence, despite the looming threat of Brexit. The country relies far more on the U.K. for trade than it does on the E.U., and many of those Scots who voted to leave the U.K. also voted to leave the E.U., leading to a complex picture.

A spokesman for the U.K.’s Prime Minister, Theresa May, said: “Another referendum would be divisive and cause huge economic uncertainty at the worst possible time.”