RIYADH- Non-Saudi investors were allocated 23% of the institutional tranche of Saudi Aramco's initial public offering (IPO), an executive at one of the lead banks on the deal told the Al Arabiya news channel on Monday.

Wassim Al Khatib, head of investment banking at National Commercial Bank also said the Saudi Public Pension Agency received an allocation equivalent to 11.5% of the Aramco IPO institutional tranche.

State-owned Aramco is expected to list 1.5% of its shares on the Saudi exchange later this week in a deal worth $25.6 billion.

(Reporting by Marwa Rashad and Davide Barbuscia, editing by Louise Heavens) ((Davide.Barbuscia@thomsonreuters.com; +971522604297; Reuters Messaging: davide.barbuscia.reuters.com@reuters.net))