Iraq 's crude oil exports from northern Kirkuk oil fields to the Mediterranean port of Ceyhan in Turkey has been on hold since Sunday. The flow was briefly resumed last week after a suspension that lasted for more than three weeks, a Middle East shipping agent said Monday.

"The flow was stopped at 1630 (local time) on Sunday," the shipping agent told Dow Jones Newswires.

Iraq was pumping between 480,000 and 600,000 barrels a day before it was stopped, he said.

The shipping agent knew nothing about why the flow was stopped. Iraqi oil officials weren't available to comment. However, Iraqi local press quoting an official as saying that a leak at one part of the pipeline inside
Iraq caused the suspension.

There are some 400,000 barrels in storage tanks in Ceyhan port, while some four vessels are waiting for loading, he said.

Iraq resumed exports from Kirkuk oil field last Tuesday after a suspension of 25 days due to a leak in the pipeline in Iraq .