By Christopher Johnson
LONDON (Reuters) - Oil prices dropped more than 1 percent on Friday, heading for a third weekly loss after Saudi Arabia warned of oversupply, while a slump in stock markets and concerns about trade clouded the outlook for fuel demand.
Brent crude oil (LCOc1) fell $1.12 to a low of $75.77 per barrel and was trading around $78.84, down $1.05, by 0950 GMT. The contract is on course for a weekly loss of almost 5 percent. It has fallen by more than $10 in the last three weeks.
U.S. crude (CLc1) was $1.05 lower at $66.28, set for a 4.1 percent loss this week.
"The energy complex is resuming its downward trajectory," said Stephen Brennock, analyst at London broker PVM Oil. "More of the same is expected in the near-term with sellers still very much on the prowl and intent on pushing prices lower."
A global collapse in equities has roiled oil markets this week as Wall Street had its biggest daily decline since 2011, wiping out all of this year's previous gains.
Financial markets have been hit hard by a range of worries, including the U.S.-China trade war, a rout in emerging market currencies, rising borrowing costs and bond yields, and economic concerns in Italy.
There are also signs of a slowdown in global trade, with container and bulk freight rates dropping after rising for most of 2018.
After many months of concern about shortage of supply ahead of U.S. sanctions on Iran, due to begin on Nov. 4, the oil market is beginning to be concerned about possible oversupply and inventories that are rising in many parts of the world.
Saudi Arabia's OPEC governor said on Thursday oil markets could face oversupply by the end of the year.
"The market in the fourth quarter could be shifting towards an oversupply situation as evidenced by rising inventories over the past few weeks," Adeeb Al-Aama told Reuters.
Saudi Energy Minister Khalid al-Falih said there could be a need for intervention to reduce oil stockpiles after increases in recent months.
For now, however, the main focus in the oil market remains on U.S. sanctions and the impact they are having on Iran's oil exports. Washington has said it wants to reduce Iranian oil sales to zero, although this looks unlikely.
Many buyers, including Iran's biggest customer, China, appear to be falling in line, forcing Tehran to store unsold oil on tankers in the hope it can sell the crude once sanctions are lifted.
(Graphic: Iran oil exports already falling - https://tmsnrt.rs/2PkSYHU)