Abu Dhabi: Abu Dhabi National Oil Co (Adnoc), the biggest oil-producer in the UAE, will resume production from its 280,000 barrel-a-day Lower Zakum West field on December 6, a company official said.

The field, which produces more than 10 per cent of the UAE's daily oil output, has been completely shut since the end of October for the installation of a gas facility.

The new facility will inject gas into the oil wells to exert pressure in the reservoir so more oil can be pumped out.

Adnoc, the second-larg-est Arab oil company by production, reduced its output this month by a quarter, or about 600,000 barrels a day, because of planned maintenance at the Upper Zakum, Lower Zakum West and Umm Shaif oilfields.

Umm Shaif has resumed production, the official, who declined to be identified because of company policy, said. Lower Zakum includes Lower Zakum West and Lower Zakum Central.

Zakum Central continues to produce about 60,000 barrels a day while the rest of the field undergoes maintenance, the official said.

Lower Zakum and Umm Shaif are operated by Abu Dhabi Marine Operating Co, also a unit of Adnoc.

An Adnoc official responsible for maintenance at the Upper Zakum field declined to confirm output at that field had resumed. Upper Zakum, which contributes about 200,000 barrels a day to UAE daily oil production, is operated by Adnoc unit Zakum Development Co.

The UAE, the third-largest oil exporter in the Organisation of Petroleum Exporting Countries, is planning to raise oil output to four million barrels a day from about 2.6 million barrels a day at present.