International Benchmark Brent crude traded at $77.49 per barrel at 0658 GMT on Monday, while American benchmark West Texas Intermediate (WTI) saw prices of $68.28 per barrel.
Brent crude traded at $76.96 per barrel at 1855 GMT on Friday, while American benchmark West Texas Intermediate was recorded as $67.83 a barrel at that time.
The rise is driven by a decrease in the U.S. oil rig count last week. The number of oil rigs in the country decreased by two for the week ending Sept. 7, according to oilfield services company Baker Hughes data on Friday.
This brought the total number of oil rigs in the U.S. to 860, from 862 the week before.
Another factor driving the price rise is the upcoming U.S. sanctions against Tehran in November, which led countries such as India, Japan and South Korea to limit energy imports from Iran.
Analysts are also monitoring the long-term effects of developments in Syria following the trilateral summit between Iran, Russia and Turkey on Friday, as well as media claims that the U.S. is plotting a coup in Venezuela.
One U.S. dollar equals 6.46 Turkish liras.
By Hale Turkes