Aberdeen (United Kingdom) – The prospects for Scotland’s economy after Brexit are at the heart of the battle between its pro-independence first minister and British Prime Minister Theresa May, who wants Britain to stay united as it leaves the EU.

Nicola Sturgeon has warned that leaving the bloc’s single market will cause tens of thousands of job losses in Scotland, while May has said she will aim for the “best possible deal” with Brussels — for Scotland too.

Going it alone raises a host of doubts about Scotland’s economy including what currency it would use and how it could reduce a budget deficit of 9.0 percent of gross domestic product — worse than crisis-hit Greece.

But the future of the North Sea oil sector — centred on the city of Aberdeen, where Sturgeon’s Scottish National Party held its conference this weekend — is the key concern.

World oil prices have declined in recent years and the offshore stocks are depleting. Deirdre Michie, head of Oil & Gas UK, the leading association for the North Sea industry, told AFP the sector was going through “quite a sustained downturn”.

© AFP Michal Wachucik Scotland's First Minister Nicola Sturgeon has warned leaving the EU's single market will cause tens of thousands of job losses in Scotland

© AFP Michal Wachucik – Scotland’s First Minister Nicola Sturgeon has warned leaving the EU’s single market will cause tens of thousands of job losses in Scotland