ConocoPhillips (COP) has shut its 71,000-barrel-a-day Whitegate refinery on the east coast of Ireland for planned maintenance, a company official said Tuesday.

The refinery was shut Aug. 26 for "four to five weeks," said the official.

Traders said the units being shut involved the 71,000-barrel-a-day crude distillation unit, but the official declined to comment on that.

The Whitegate refinery, in Cork harbor, is the only refinery in Ireland.

-By Sherry Su, Dow Jones Newswires; +44(0)20-7842-9329; sherry.su@dowjones.com

(Reza Amanat contributed to this story.)