DUBAI: National Commercial Bank , Saudi Arabia's biggest lender, has tightened the price guidance for Tier 1 US dollar-denominated sukuk by 37.5 basis points to around 3.75%, a document showed on Wednesday.

NCB is seeking to raise $1 billion through the perpetual Islamic bonds, two financial sources said. It has received over $4.8 billion in orders for the sukuk, according to the document from one of the banks arranging the deal, which is expected to close later on Wednesday.