The president of Catalonia's regional government went on trial in Barcelona on Monday for "disobedience" after refusing to remove separatist symbols from public buildings, amid heightened tensions in the Spanish region.

Prosecutors have called for Quim Torra to be fined 30,000 euros ($33,000) and declared ineligible for public office for 20 months, which would make it impossible for him to remain president and likely trigger an early election in the wealthy northeastern region.

But his ineligibility would only come into effect if the sentence is confirmed by Spain's Supreme Court, which could take months.

Torra's one-day trial opened after Spain's Supreme Court on October 14 sentenced nine Catalan separatist leaders to lengthy jail terms over an abortive 2017 independence bid, setting off a wave of angry protests that repeatedly descended into violence.

In March, Spanish electoral authorities ordered Torra to remove separatist symbols to respect institutional neutrality ahead of parliamentary elections in April.

They objected in particular to a banner outside the Catalonian regional government headquarters that read "Freedom for political prisoners and exiles" next to a yellow ribbon indicating support for the detained Catalan separatist leaders who were sentenced last month.

Catalan regional president Quim Torra told the court in Barcelona he had disobeyed orders from electoral authorities to take separatist symbols down from public buildings
Catalan regional president Quim Torra told the court in Barcelona he had disobeyed orders from electoral authorities to take separatist symbols down from public buildings POOL / Andreu DALMAU

The Catalan government ignored two deadlines to take the banner down before finally ceding just before a planned police intervention.

"I did not respect (the order from the electoral authorities) or put another way, I disobeyed," Torra told the court, speaking in Catalan.

But he argued the electoral authorities did not have the "competence" to give the order to take down the symbols, because they are "not higher on the hierarchy than the president" of Catalonia.

Many pro-independence supporters, including Torra, have adopted a yellow ribbon to protest the arrest and jailing of the Catalan separatist leaders over the 2017 independence bid.

The yellow ribbon "is not propaganda" but instead expresses a "desire for justice", Torra told the court.

Referring to the jailed Catalan separatist leaders as "political prisoners" was a question of "freedom of expression", he added.

Catalonia's parliament and its regional government are dominated by separatist parties, but the region itself remains deeply divided and the recent crisis has exacerbated the split.