ADIB, one of Abu Dhabi's smaller banks by market value, made the loan to Saad in 2007 to finance an investment in an Abu Dhabi warehousing company that did not become operational, according to the report.
ADIB officials were not immediately available for comment.
In recent weeks, several banks in the region have offered details on their exposure to Saad and another Saudi family firm, Ahmad Hamad Al Gosaibi Group & Brothers (Ahab), which are facing a debt crisis.
In the UAE, at least five banks, including Mashreq, National Bank of Abu Dhabi, and Abu Dhabi Commercial Bank have exposure to the Saudi firms, according to banking sources or the banks themselves.
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