Spain is about to receive an emergency disbursement from the 100 billion-euro ($123 billion) bailout of its financial system because of restrictions the European Central Bank imposed on bank borrowing, according to a person familiar with the matter.

The ECB last month imposed limits on how much it will lend banks against government-guaranteed bonds. The rule change meant Spain had to ditch a plan for nationalized lender Bankia group to get a loan from the Frankfurt-based central bank, said the person, who asked not to be named because the matter is private.

Bankia group, formed in 2010 from the merger of Spain's troubled savings banks, will now get the first portion of the country's European Union cash imminently, the person said. The rescue program always included a 30 billion-euro tranche to be paid out first and "mobilized in any contingency," according to the agreement document dated July 16.