Gulf International Bank, which is owned by Saudi Arabia's sovereign wealth fund, has initiated 5-year bond sale, a bank document seen by Reuters showed on Wednesday.

The Manama-headquartered lender has set initial price guidance at around 150 basis points over U.S. Treasuries, the document showed.

The bank plans to sell U.S. dollar-denominated senior unsecured 5-year bonds under GIB’s existing $2.5 billion Euro Medium Term Note Programme.

The deal is reported to be benchmark-sized, which usually understood to be at least $500 million.

Saudi Arabia sold a $5 billion Islamic bond, or sukuk, in three tranches on Tuesday amid strong investor demand for the kingdom's debt.

(Reporting by Mohammad Edrees; editing by Jason Neely)