Tens of thousands of people marched through Barcelona on Sunday to protest against plans to grant Catalan separatists an amnesty in exchange for their political support for a new left-wing government.

Many of the protesters waved Spanish and Catalan flags or signs saying "No Amnesty!" as they flooded into the city center.

Police said the crowd was 50,000 strong, while organizers — Societat Civil Catalana (SCC), a civil society group opposed to the region breaking away from Spain — put the figure at 300,000.

Acting Prime Minister Pedro Sanchez' of the Socialist bloc is trying to secure a new term in office and must strike a deal with the Junts and Esquerra Republicana de Catalunya parties to gain enough parliamentary support.

Jailed separatist leaders, activists would be freed

The amnesty deal would see charges dropped against more than a thousand Catalan separatists who are facing legal action for the 2017 independence bid. Many of those involved are already in jail.

The proposal has drawn a furious response from the right and the far-right, as well as from some within Sanchez's own Socialist party, who say an amnesty cannot be used as a bargaining chip for him to remain in power.

Alberto Nunez Feijoo, leader of the opposition conservative People's Party and Santiago Abascal, leader of the far-right Vox party attended Sunday's march, telling the crowd:

"This is not an amnesty that seeks reconciliation. The only thing it seeks is to make [Sanchez] the head of the government."

Abascal denounced the plan as "an assault on the Constitution," accusing Sanchez of carrying out "real abuses" in order to stay in power.

Inconclusive election led to months of wrangling

Spanish politics has been in limbo since the inconclusive election in July.

The People's Party won the most seats but even with the support of Vox failed to secure a parliamentary majority.

Despite months of subsequent negotiations, Feijoo was unable to gain the support of smaller parties to form a governing coalition.

This week, King Felipe VI gave Sanchez permission to seek the backing of other political parties for a new mandate.

To win the parliamentary vote, he needs the backing of seven lawmakers from a hardline Catalan separatist party that has demanded the amnesty.

Sanchez has defended his conciliatory policy with Catalonia, including a 2021 pardon to nine jailed leaders, and said the 2017 crisis "brought nothing good."

Most Spaniards against amnesty

But the amnesty deal doesn't have the support of most Spaniards, according to a poll last month. 

Around 70% of respondents — 59% of them Socialist supporters — said they were against the idea of an amnesty.

If no candidate for prime minister secures a majority by November 27, a repeat election has to be called.

mm/lo (AFP, Reuters)