Spain's main banking associations warned Friday that a victory for Catalonia's secession drive would create severe banking problems for the new Mediterranean nation left outside the European Union.

The associations stopped short of saying their member banks would leave Catalonia, but said in a statement that financial institutions in the region "would face serious problems of legal uncertainty" if the highly industrialized northeastern region with 7.5 million people went independent.

The Spanish Banking Association and the Spanish Confederation of Savings Banks said independence for Catalonia could prompt banks to "reduce banking supply," causing a financial and credit crunch.

Voters in Catalonia on Sept. 27 will elect regional lawmakers.

Pro-secession parties are trying to win a majority in the 165-seat parliament so they can set Catalonia on a path toward a unilateral independence declaration in 2017.

They wanted to stage an independence referendum in Catalonia but the central government in Madrid didn't allow it.

Spanish Prime Minister Mariano Rajoy has repeatedly insisted that Catalonia will not be allowed to secede because independence for the region is unconstitutional.

The banking associations urged political leaders for and against Catalonia independence to engage in dialogue to achieve "better levels of well-being and social cohesion for all."

Two of Spain's major banks are headquartered in Catalonia — Banco de Sabadell SA and Caixabank SA.

Secession leaders insist a way may be found for an independent Catalonia to stay within the eurozone or continue using the euro.

But European leaders, ranging from Rajoy to Britain's David Cameron and the executive arm of the European Union, have said any region like Catalonia that breaks away from an EU member state will be out of the EU and forced to apply for membership.