Catalans will vote in an independence referendum, regional foreign minister Raul Romeva told AFP Tuesday, despite a crackdown by Madrid which wants to prevent a vote deemed unconstitutional by the courts.

"People will go out and vote en masse, peacefully on Sunday," said Romeva, in charge of foreign affairs in the separatist Catalan government led by Carles Puigdemont, who is determined to hold the vote on October 1 despite a court ban.

"I don't have any doubt."

Over the past days, judges and prosecutors have ordered the seizure of electoral material including millions of ballot papers, the closure of websites linked to the vote and the detention of key members of the team organising the referendum.

The electoral board set up to oversee the vote has been dissolved, and on Tuesday prosecutors ordered police to seal off places to be used as polling stations and guard them until Sunday.

"Every time they have tried to prevent something from taking place, we have found a solution," Romeva said.

"We can guarantee that everything needed to vote is there.

"We can go back and print ballot papers as many times as needed, we have the electoral roll, ballot boxes and there will be polling stations."

He gave no further details.

Spain has deployed thousands of police to Catalonia to prevent the vote from taking place, arguing it is illegal and needs to be stopped.

According to Romeva, tasked in 2016 with preparing the ground abroad for a potential independent Catalonia, "the state's response has European institutions and capitals of EU states very concerned."

He would not be drawn further.

But at least openly, Catalonia's separatist leaders have very little support abroad as foreign leaders side with the Spanish government's attempts to maintain the law and the country's unity.

However Scottish First Minister Nicola Sturgeon, the influential leader of the pro-independence Scottish National Party, last week expressed concern over Madrid's rejection of "the right of a people to democratically express their will."

Romeva said he hoped the international community would speak out after the referendum.

"In the past 25 years, of the 53 self-determination referendums that have taken place, no state positioned itself before the referendum," Romeva said.

"There has always been a reaction afterwards. And in this case it will be exactly the same."

Source: AFP