Trading of shares in Abu Dhabi Commercial Bank, Union National Bank and Abu Dhabi Islamic Bank were suspended on Sunday. The shares jumped last week because of renewed speculation that the Abu Dhabi government might engineer a merger between ADCB and UNB, and another between ADIB and Al Hilal Bank. Both moves would be part of an efficiency drive. There was no immediate official statement from the banks, but banking industry sources said the banks were expected to send statements denying that they had plans to merge.