A SENSATIONAL new poll which The National is publishing on the eve of the Catalan independence referendum shows an upsurge in support for independence that varies dramatically depending on whether or not Spain’s central government boycotts the vote.

The telephone poll was carried out over the last three weeks and completed on Thursday, but the results could not be published in Catalonia. They were released to The National yesterday.

Two scenarios were put to a sample of nearly 3300 voters: “With the current situation in Catalonia, with Spanish government and main Spanish political parties calling for a boycott of the referendum,” and “a referendum agreed with the Spanish authorities”.

If the Spanish Government were to boycott the referendum, 62 per cent would turn out to vote, with more than 2.7 million votes for YES, and around 527,000 for NO

With the boycott in place, 62 per cent of voters would turn out, said the poll, with 38 per cent abstaining.

In this scenario, a massive 83 per cent would vote Yes, while 16 per cent would say No. Two percent of responses were null. The total Yes votes would be more than 2.7 million, with 527,000 No voters.

However, the percentage of No voters rises significantly in the second scenario, which would see a total turnout of 77 per cent and 23 per cent abstaining. Of these, 32 per cent would vote No, while two thirds (66 per cent) would vote Yes.

With no boycott of the referendum by Spanish authorities there would be a rise in turnout of 15 per cent, to a 77 per cent turnout. The YES vote would fall by 17 per cent to 66 per cent, but would still be more than double the NO vote

This electoral studies centre survey shows a marked rise in support for independence, regardless of whether Madrid approves or not.

Recent polls have shown indy support amongst Catalans struggling to rise above 50 per cent, with most results around 40-46 per cent. The new poll results could be an indication of dissatisfaction with the strong-arm tactics of Spanish Prime Minister Mariano Rajoy to stop the plebiscite.

Jordi Sanchez, president of the Catalan National Congress, welcomed the results and told The National: “This poll confirms there’s a majority of people that want to vote and will vote, and this can’t be stopped by any police or state of emergency.

“The only solution will come through voting, applying the results, and dialogue.” The poll came as an international delegation of parliamentarians arrived to observe the referendum at the invitation of the Public Diplomacy Council of Catalonia (Diplocat).

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A total of 33 representatives from 17 countries comprise the delegation, including SNP MPs Joanna Cherry and Douglas Chapman, and Hywel Williams, Plaid Cymru MP and chair of the All Party Parliamentary Group (APPG) on Catalonia.

Diplocat said some of the group have expressed concern about the violation of civil rights Catalonia, and have said they wanted the vote to take place without any problems.

The party met Catalan ministers yesterday, along with civic society organisations.

Today they are expected to meet representatives from across Spain’s political spectrum.

The Catalan Government, meanwhile, has unveiled some of the logistics it hopes will allow tomorrow’s vote to go ahead.

Its spokesman said yesterday that 5.3 million people will be called to vote at 2,315 polling stations – with more than 6,000 polling places – throughout Catalonia.

He added that the referendum would be supervised by over 7,200 people from among more than 50,000 who responded to a government call for volunteers last month.

Oriol Junqueras, Catalonia’s vice-president, said if Spanish police prevented polling stations from opening, people called to vote at those sites would still be able to vote, although he did not disclose how, or where.

Clara Ponsati, the St Andrews University professor on secondment as Catalan Education Minister, told the heads of schools being used as polling stations she was relieving them from responsibility for their sites until after the vote.