CNOOC Ltd's Nexen unit is shutting operations at an oil field and processing facility in Yemen due to a security threat, a Nexen spokeswoman said on Sunday.
The spokeswoman said Nexen determined there is an undue risk for staff working at its Block 51 field operations and BAK PF processing facility in Yemen.
"As a prudent operator, we are temporarily shutting-down Block 51 PSA field facilities to ensure the safety of our people. The shut-down will be progressed in a timely manner. Our personnel will vacate and production will cease," Nexen spokeswoman Diane Kossman said in an e-mail.
She said Nexen will monitor the situation and re-start operations when it is safe for workers to return.
China's CNOOC acquired Calgary, Alberta-based Nexen in early 2013.
(Reporting by Jeffrey Hodgson in Toronto; Editing by Diane Craft)