DUBAI- National Commercial Bank, Saudi Arabia's biggest lender, has set the yield for Tier 1 U.S. dollar-denominated sukuk at 3.5%, a document showed on Wednesday, which will be the lowest-ever launch yield for perpetual bonds from the Gulf.

It received over $5.3 billion in orders for the perpetual Islamic bonds, for which it had given initial price guidance of around 4.125% earlier on Wednesday, documents from one of the banks arranging the deal showed.

NCB is seeking to raise $1 billion via the sukuk, two financial sources said. The deal is expected to close later on Wednesday.

(Reporting by Yousef Saba; Editing by Steve Orlofsky) ((Yousef.Saba@thomsonreuters.com; +971562166204))