Oil prices rose slightly in international markets after the US threatened to extend its naval blockade of Iran indefinitely, raising fresh concerns about global oil supply.
Oil prices had fallen more than 2 percent in the previous session on fears of a drop in global demand.
Brent and US West Texas Intermediate (WTI) crude both fell more than 2 percent on Thursday, snapping a series of gains for both benchmarks.
However, both are still on track to rise about 4 percent this week.
Brent futures rose 9 cents, or 0.1 percent, to $87.16 a barrel on Friday (August 14). WTI crude rose 4 cents to $81.29 a barrel.
Meanwhile, US Treasury Secretary Scott Besant said that Washington is going to take some steps against Iran that have never been seen before.
In an interview with Newsmax, Besant said that more announcements could come next week. Measures will be taken to isolate Iran economically, which is unprecedented in the history of economic isolation against any country.
He also said that this will be accompanied by a continued naval blockade of the Strait of Hormuz. As a result, no goods or ships will be able to enter or leave Iranian ports.
The threat of a prolonged blockade there, as a large amount of energy is transported through one of the world's most important oil transportation routes, has further increased concerns about supply in the international oil market.
