Support for a second independence referendum in Scotland could surge in the event of a no-deal Brexit, an expert on Scotland’s relationship with the EU has said.

Kirsty Hughes, director of the Scottish Centre on European Relations (SCER), has said a hard or no-deal Brexit could “potentially be a trigger…for a new independence referendum".

In a new SCER paper, Brexit Uncertainty, Scotland and the UK in 2018, Dr Hughes considers four Brexit scenarios and their impact on Scotland.

The paper predicts that support for independence could surge in the event of a no-deal or hard Brexit, and that the parties who oppose tumbling out of the EU without a deal might come to power in the event of an early general election in 2018 or 2019.

“One possible outcome for a crisis election would be that the Liberal Democrats, along with the Scottish National Party, could end up holding the balance of power,” Dr Hughes wrote.

On the other hand, the paper says a soft Brexit would significantly undermine any case for an urgent second independence referendum.

Now a no-deal Brexit seems a serious possibility, we could end up staying in the EU after all

It also calls for greater clarity on Brexit policy from both Labour and the SNP.

"Labour cannot simply stick to Brexit vagueness, pretending opposition to hard Brexit. Both Labour and the SNP need to think through whether to support a second EU referendum [on the terms of the deal]," the document says.

"The current support for Brexit by the Tories and Labour in Scotland did them no harm in the 2017 election but that might change rapidly amidst the chaos of a ‘no deal’ scenario."

According to the What Scotland Thinks poll aggregator, which takes a rolling average of all polls conducted on the independence question, 50 per cent of Scots would vote ‘No’ to independence, compared to 30 per cent who would vote ‘Yes’.

The Scottish National Party insists it still has a mandate to hold a second independence referendum before the next Holyrood elections in 2021.

However, party leader Nicola Sturgeon has repeatedly refused to set a date for an independence vote until the outcome of Brexit becomes clear.

The report comes as the UK government has been criticised for not publishing any research on the impact of Brexit in Scotland.