UPDATE 1-Shell delays restart of Pernis oil units -sources

(Adds FCC)

LONDON, Nov 3 (Reuters) - Royal Dutch Shell (RDSa.L) has delayed the restart of oil units at its Pernis refinery in the Netherlands by about two weeks, trading sources said on Monday.

Shell shut about three refining units, including one crude distillation unit (CDU), in mid-September for planned maintenance.

The CDU, which can process about 200,000 barrels of crude oil per day, is now expected to restart on Nov. 17, they said. In mid-August another source had said the maintenance would be completed this week.

The sources said they did not know the reason for the delayed restart.

A Shell spokesman declined to comment.

The total capacity of Pernis is 412,000 bpd and it is the largest oil refinery in Europe.

A fluid catalytic cracker (FCC) at Pernis, which was unexpectedly shut in late September for a mechanical problem, would be restarted around the same week, the trading sources said. (Reporting by Ikuko Kao, Editing by Peter Blackburn)