Shell and Total have slashed their Syrian oil exports as oil sanctions make exports all but impossible.
The news comes as the international community considers widening the current sanctions in place against the Assad regime, which the UN estimates has killed 3,500 protestors since civil unrest broke out early this year.
The Assad regime has relied on oil for up to a third of its revenue, and has enjoyed wides discretion over how to apply the proceeds.
UK independent Gulfsands announced a sharp drop in production last month, as Polish firm Kulczyk Oil announced it was suspending operations. Gulfsands reported that the Syrian Oil Ministry had ordered that production be cut sharply as domestic inventories rose to capacity.
A second oil industry source confirmed to the Reuters news service that this was affecting production at Shell’s joint venture and a third source said it had impacted Total’s investments.
Syria produced around 350,000 barrels per day before the unrest, of which about a third was exported, with most flows going to Europe.