BREXIT and Nicola Sturgeon’s handling of the pandemic are still the main driving forces behind a surge in support for independence.

That’s according to polling expert John Curtice, who suggested the UK Government’s Internal Market Bill has further weakened the case for the Union.

The legislation, which will give Westminster oversight on devolved policy areas, has been branded a power grab by the Scottish Government. Only the Tories backed the proposals as they were rejected by MSPs in a vote last week.

Professor Curtice gave his thoughts after two surveys published over the weekend recorded rising support for a Yes vote.

The research, commissioned by Progress Scotland, found 64% of respondents with a view believe Scotland would vote Yes if a referendum was held now. It also suggested a third of Scots are more likely to back independence in a future referendum as a result of the UK Government’s power grab.

READ MORE: Record level of Scots believe Yes would win in referendum

Around half also said the Internal Market Bill makes no difference to their opinion on the constitutional question, which Curtice believes is evidence the Yes side has not yet fully capitalised on negative sentiment towards the proposals.

He told the Record: "The Internal Market Bill sees both sides deliberately talk past each other, because they are comparing the proposals with different base lines.

"Boris Johnson says he is giving more Scotland more powers – but he saying that from a Brexit perspective. But if you are a devolutionist, or a nationalist, you are asking what would happen if the principle of the 1998 Scotland Act was still operating – and that would be Holyrood gains even more power.

"The point is, because they are talking past each other, the public in many cases are struggling to follow the argument. Compared to even Brexit, it is very complicated.”

He added: "It's a development that doesn't help the Unionist side, that much is clear. But it's not clear it's a particularly strong vote-winner for the nationalist side either."

READ MORE: Brexit Internal Market Bill pushing one-third of Scots towards Yes

The Progress Scotland polling is nevertheless indicative of increased support for the pro-independence side, Curtice said.

"It is consistent with the evidence of other polls which is that Yes has gained ground in recent months,” he explained.

A total of 73% of those surveyed in the research thought Brexit makes Scottish independence more likely. Respondents also tended to say the First Minister has handled the crisis more adeptly than Boris Johnson. 

Asked what is propelling the surge in support for Yes, the professor answered: "It's two things – it's Brexit, and it's coronavirus."