"The banks have resigned themselves to the fact there is nobody else left to inject money," the source said, adding that each bank had yet to finalise the exact sum to be handed over.
According to the Expansion business daily, the banks are willing to lend Abengoa a total of €113 million ($122 million), preserving its cash flow until mid-January, and allowing it to pay salaries and Christmas bonuses this month.
It identified the creditor banks as Spain's Banco Santander, Bankia, Banco Sabadell, Banco Popular, CaixaBank, French bank Credit Agricole and Britain's HSBC plus the public credit body ICO.
The deal is to finalised next Wednesday, the paper said.
In return, Abengoa will put up a 28-percent stake in its US subsidiary Abengoa Yield as collateral, added the Cinco Dias newspaper.
The group filed for protection from its creditors late last month, giving it four months to find a solution to its astronomical debt, or go bankrupt and become Spain's biggest-ever corporate failure.
With just two days until Spain votes in a general election, Prime Minister Mariano Rajoy has yet to comment on the possibility of a Spanish company that employs 28,700 people globally - including nearly 7,000 at home - going under.
The government has ruled out any form of state bailout, with Economy Minister Luis de Guindos stressing the need "to find out exactly what the accounting and debt situation of the company is".