Supporters of right wing VOX party hold Spanish flags during a speech of their leader Santiago Abascal in a campaign rally in Barcelona, Spain, Thursday, Oct. 31, 2019. Spain's political parties are kicking off their electoral campaigns Thursday ahead of a Nov. 10 ballot that will take place amid renewed tensions over the future of the restive Catalonia region. (AP Photo/Emilio Morenatti)

MADRID (AP) — Hours before the start of campaigning for Nov. 10 national elections, Spain's interim justice minister on Thursday urged parties to refrain from exploiting tension in the country's restive Catalonia region to reap political benefits.

Spanish parties "should be capable of not turning (Catalonia) into a partisan or electoral issue" and be "loyal to the state," Dolores Delgado told The Associated Press in an interview.

She added that only extremists would gain from further tension.

Spain's fourth general election since 2015 follows failed negotiations to form a government between the Socialists — who came first in the last, April 28 election — and the anti-austerity Podemos (We Can) party.

Interim prime minister Pedro Sánchez, the Socialist leader, is ahead in the polls but has lost steam as support grows for the conservative opposition Popular Party and the surging Vox far-right party.

Campaigning officially starts at midnight Thursday. It will only last 8 days after the electoral law was changed to avoid a splurge of funds in the case of a repeated ballot.

The debate is expected to focus on Catalonia.

The crisis over roughly half of the region's 5.5 million voters' desire to secede from Spain revived this month with protests — many marred by violence — over the imprisonment of separatist leaders.

The rioting, mostly in the northeastern region's capital of Barcelona, left more than 600 people injured and police arrested dozens of protesters.

The right-wing opposition has accused Sánchez of relying on the separatists' votes to gain office and are calling for a heavier hand to crush what they call a "coup d'état" by Catalan separatists.

Vox has gone one step further, calling for suspending the region's self-government and outlawing separatist parties.

In April, Vox became the first Spanish nationalist party to enter parliament in nearly four decades. Its leaders chose a town near Barcelona to hold their first campaign rally on Thursday evening.

Sánchez's government has refused to talk to the region's separatist leaders until they explicitly condemn the rioting and listen to Catalans who oppose secession.

Delgado, the justice minister, said that by convicting the leaders of the 2017 independence bid the country's top court dealt only with the part of the crisis where Catalan leaders used their power to "break the legal order."

"But there is also a political problem. There is a problem of dialogue. We must establish the norms for developing that dialogue to re-establish coexistence" between those in favor and those against independence, she said. "But with violence, that is impossible."

More protests are expected ahead and after the general election. Tsunami Democratic, a secretive Catalan group with hundreds of thousands of online followers, has called for gatherings on Nov. 9, the eve of the ballot.

The group is under investigation after one of its earlier calls for action resulted in a siege of Barcelona's international airport that ended in clashes.

Asked about the prospect of an election marred by protests, Delgado said "political extremes" were the most interested in stirring trouble.

Spain's interim justice minister Dolores Delgado during an interview with The Associated Press at the Ministry of Justice in Madrid, Spain, Thursday, Oct. 31, 2019. Spain's interim justice minister says that political parties should stay away from turning the crisis in Catalonia into a political weapon during campaigning for the upcoming Nov. 10 general election, which begins at midnight on Thursday.(AP Photo/Manu Fernandez)
Spain's interim justice minister Dolores Delgado during an interview with The Associated Press at the Ministry of Justice in Madrid, Spain, Thursday, Oct. 31, 2019. Spain's interim justice minister says that political parties should stay away from turning the crisis in Catalonia into a political weapon during campaigning for the upcoming Nov. 10 general election, which begins at midnight on Thursday. (AP Photo/Manu Fernandez)
Spain's interim justice minister Dolores Delgado during an interview with The Associated Press at the Ministry of Justice in Madrid, Spain, Thursday, Oct. 31, 2019.  Spain's interim justice minister says that political parties should stay away from turning the crisis in Catalonia into a political weapon during campaigning for the upcoming Nov. 10 general election, which begins at midnight on Thursday.(AP Photo/Manu Fernandez)
Students sit next to their tents set up at University square as they block one of the main avenues in Barcelona, Spain, Thursday, Oct. 31, 2019. Hundreds of young people decided to set up camp after Spain's Supreme Court convicted 12 separatist leaders of illegally promoting Catalonia region's independence and sentenced nine of them to prison. (AP Photo/Emilio Morenatti)
Material to be used during the upcoming Spanish general elections is stored at a warehouse in Alcala de Henares, outskirts Madrid, Spain, Thursday Oct. 31, 2019. Spain's political parties are kicking off their electoral campaigns Thursday ahead of a Nov. 10 ballot that will take place amid renewed tensions over the future of the restive Catalonia region. (AP Photo/Bernat Armangue)
Ballot papers for Spain's pro-animal rights party PACMA are stored at a warehouse in Alcala de Henares, outskirts Madrid, Spain, Thursday Oct. 31, 2019. Spain's political parties are kicking off their electoral campaigns Thursday ahead of a Nov. 10 ballot that will take place amid renewed tensions over the future of the restive Catalonia region. (AP Photo/Bernat Armangue)
A ballot paper for Spain's PSOE Socialist Party is stored at a warehouse in Alcala de Henares, outskirts Madrid, Spain, Thursday Oct. 31, 2019. Spain's political parties are kicking off their electoral campaigns Thursday ahead of a Nov. 10 ballot that will take place amid renewed tensions over the future of the restive Catalonia region. (AP Photo/Bernat Armangue)
Workers load ballots from Spanish political parties at a warehouse in Alcala de Henares, outskirts Madrid, Spain, Thursday Oct. 31, 2019. Spain's political parties are kicking off their electoral campaigns Thursday ahead of a Nov. 10 ballot that will take place amid renewed tensions over the future of the restive Catalonia region. (AP Photo/Bernat Armangue)
Students protest during a demonstration in Barcelona, Spain, Thursday, Oct. 31, 2019. Hundreds of young people decided to set up camp after Spain's Supreme Court convicted 12 separatist leaders of illegally promoting Catalonia region's independence and sentenced nine of them to prison. (AP Photo/Emilio Morenatti)
The leader of the right wing VOX party Santiago Abascal smiles during a campaign rally in Barcelona, Spain, Thursday, Oct. 31, 2019. Spain's political parties are kicking off their electoral campaigns Thursday ahead of a Nov. 10 ballot that will take place amid renewed tensions over the future of the restive Catalonia region. (AP Photo/Emilio Morenatti)