Abu Dhabi National Oil Co (Adnoc) has notified more Asian term lifters it will sharply cut November exports of its three offshore crudes due to oilfield maintenance, trading sources said.

Adnoc, the main oil producer for UAE, an Opec member, notified a Japanese lifter that its supply of Umm Shaif, Lower Zakum and Upper Zakum crude grades for November would be zero, compared with full contracted volumes for October, a source said.

Another lifter also has received a notice that it would not get supplies of Lower Zakum for November, another source said.

That represents a deeper cut in supplies after Adnoc earlier this week had told a third Japanese lifter that it would halve term November exports of the three grades, Umm Shaif, Lower Zakum and Upper Zakum.

A separate industry source said one Taiwanese lifter has not yet received a notice from Adnoc, but added that it did not expect a supply cut for the three grades as deep as 50 per cent.

Despite the deep cuts, the supplies of Murban crude will remain steady at full contracted volumes for November to the  Japanese lifters, the same as for October, trading sources said.

The emirate, which pumped about 2.6 million barrels per day (bpd) last month, is reducing exports for November, denting the impact of Opec's planned output rise.

Adnoc said on Sunday that oilfield maintenance would reduce oil production by 600,000 bpd in November.

Oil traders had earlier said as much as 810,000 bpd of output could be shut in for two to three weeks during the peak of the maintenance.

The three fields, in which Exxon Mobil, Total and BP hold equity stakes, produce a total of just over 1 million bpd, according to recent estimates. Reuters