Spain is planning to inject billions of euros into the nation's struggling savings banks, known as cajas, according to a report from the Wall Street Journal.
The move appears to be an attempt to calm investor fears that the banks are unable to raise their own funds, the paper said.
In addition, sources told the Journal, Spain will likely move to simplify the structures of the banks, many of which feature complex ownership structures and disclose little financial information.
The Spanish Finance Ministry, contacted by CNBC, refused to comment.
The Bank of Spain, which is in charge of the restructuring fund for banks, declined to comment on reports that it's planning a bond issue of up to 3 billion euros ($4 billion).
Last month, credit rating agency Moody's put Spain's debt on review for a downgrade.