Scottish First Minister Nicola Sturgeon's renewed push for secession from the UK faces several hurdles if her nationalist party's dream of independence is to come true, analysts said Thursday.

Sturgeon announced Wednesday that she will push for a second independence referendum, to be held before May 2021, saying Scotland should have the option of staying in the European Union as a separate nation.

Sturgeon leads the left-wing, separatist Scottish National Party, which has its spring conference this weekend.

In the 2014 referendum, some 55 per cent said Scotland should not be an independent country, but the dream still burns brightly within the SNP, which runs a minority government in the devolved Scottish parliament.

Daniel Kenealy, a politics lecturer at the University of Edinburgh, said the SNP was not as united on the independence drive as it likes to present.

He said newer members energised by the 2014 referendum were keen for another plebiscite soon, convinced they will win - while a more gradualist element within the party was more cautious.

"There's a real tactical disagreement in the party on how best to progress this issue," he told AFP. 

There was a "real possibility" that Spain would veto Scotland joining the EU if it held an independence vote without London's consent

He said Sturgeon's announcement was targeted at keeping independence "at the forefront of people's imaginations" in Scotland.

Kenealy said the nationalists thrive on a message of Scottish interests being impeded by London.

The British government swiftly ruling out granting a referendum re-run "is just money in the bank for the SNP".

Brexit and EU

In the 2016 Brexit referendum, 62 per cent of voters in Scotland wanted the UK as a whole to remain in the EU.

Professor Murray Pittock of the University of Glasgow, who has written extensively on the Scottish independence question, said a soft Brexit would weaken the chances of a second Scottish referendum.

"It's likely that there will be another independence referendum; whether that occurs before 2021 is another matter, and that seems unlikely," he told AFP.

He said Sturgeon would not hold an unauthorised referendum without the consent of the British government.

Pittock explained there was a "real possibility" that Spain would veto Scotland joining the EU if it held an independence vote without London's consent, as Madrid could not recognise a Catalonian independence referendum held on those terms.

Both Kenealy and Pittock said the announcement of citizens' assemblies to debate independence issues was smart politics by Sturgeon.

The assemblies could find areas of common ground with unionists for greater Scottish autonomy - and also expose fired-up nationalists to the scale of the opposition they face.

The experts also said the way the devolved administrations had been largely sidelined in the Brexit process had only fuelled Sturgeon's argument.

Public opinion unchanged

Jackson Carlaw, interim leader of the Scottish Conservative Party, the main opposition in the Scottish Parliament, said Sturgeon and her fellow travellers this time were "largely journeying on their own".

"There simply isn't the consensus that existed in 2011 when every political party accepted that the question of Scottish independence needed to be asked," he wrote in The Times newspaper.

The Scotsman newspaper's editorial said Sturgeon could not simply keep asking the independence question over and over.

"Those plans should stay on the shelf until there is a sign of a substantial shift in public opinion," it said.

Polls have shown almost no movement on independence since the 2014 referendum.

With Scottish independence as with Brexit, Pittock said opinions on both sides had hardened since the close referendum outcomes.

"The lesson is if you don't want them to be re-run, address the large minority who have lost and find some solution which goes a significant way to achieving their goals without letting down the majority," he said.

"Polarisation creates a bad legacy."

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