Reuters cited al-Sayegh as saying to reporters on the sidelines of a conference in the capital of the UAE, "Commissioning has started and will be completed by the end of this year."
The Ruwais refinery expansion would have more than double the capacity of from 415,000 barrels a day (bpd) and will process Abu Dhabi’s Murban crude oil grade.
A member of the Organisation of Petroleum Exporting Countries, UAE had planned to complete the refinery expansion program in the first quarter of 2014.
"You have to appreciate that this is a mega project and it is a long process," Sayegh added.
