The main reasons are the lack of strict quarantine measures to counter the spread of COVID-19 in 2021.
Saudi Aramco said it would lower prices for all grades of crude for buyers from Asia and the Mediterranean in October.
OPEC+ kept its plan to increase oil production by 400 thousand barrels per day per month.
The decline lasted six straight sessions, the longest such period since February 2020.
Oil prices are falling on signals that a new strain of the Delta coronavirus has begun to negatively affect the Chinese economy.
Oil is slightly cheaper on Monday after a significant rise in quotations on Friday.
The volume of electricity production by enterprises of the IPS of Ukraine is 6.6% less compared to the corresponding period of 2019.