Dubai Islamic Bank (DIB) has mandated five banks for an Islamic bond, or sukuk, due to be issued at the end of May, three sources familiar with the matter told Reuters on Tuesday. The lender has picked HSBC, National Bank of Abu Dhabi, Emirates NBD, Deutsche Bank and itself for the deal, the sources said, requesting anonymity. One of the sources added the sukuk was likely to be a benchmark-sized, five-year issue. Benchmark usually means at least $500 million. Two of the sources said the sukuk was expected to launch at the end of May. Strong regional interest and significant global Islamic liquidity are likely to support any potential issue from the bank. DIB\'s Islamic mortgage unit Tamweel priced a $300 million sukuk in January which is fully guaranteed by DIB.