ABU DHABI, Jan 12 (Reuters) - Gulf OPEC producers plan to keep their oil output in the first quarter of 2018 below the year-earlier level despite strong demand growth and a decline in global inventories, a senior OPEC source familiar with Gulf oil thinking said on Friday.
"Gulf oil producers want to make sure that the excess in commercial oil inventories which was built over the past three years will be wiped out completely," the source said.
"The joint OPEC, non-OPEC monitoring committee headed by Saudi Arabia will continue to monitor the market and make sure all countries are adhering to their cuts," the source added.
The joint ministerial monitoring committee, known as the JMMC, is due to meet next in Oman on Jan. 21.
The Organization of the Petroleum Exporting Countries and other producers including Russia are cutting oil output by 1.8 million barrels per day under a pact running until the end of 2018.
(Reporting by Rania El Gamal; Editing by Dale Hudson)