Aabar Investments has taken a €3.6 billion five-year loan.
The funds will be used to refinance debt.
Aabar is a subsidiary of International Petroleum Investment Company (IPIC).
Bank of America-Merrill Lynch, BNP Paribas, HSBC, Intesa Sanpaolo, JPMorgan, National Bank of Abu Dhabi, Natixis, Société Générale and Sumitomo Mitsui Banking Corporation acted as lenders.
The deal is the largest Euro denominated loan ever taken out by a Middle East borrower.