Transmission of the novel virus has surged throughout parts of the world and a growing number of people are working from home.
These reasons were sufficient for the IEA to lower its forecasts.
Oil demand was quick to recover from the heavy losses incurred in April when much of the world was placed under lockdown to curb the Covid-19 virus transmission.
But the International Energy Agency said in its latest monthly report it expected the recovery in demand "to decelerate markedly in the second half of 2020, with most of the easy gains already achieved".
"The economic slowdown will take months to reverse completely, while certain sectors such as aviation are unlikely to return to their pre-pandemic levels of consumption even next year," it said.
It also warned that a potential second wave of the virus could propel governments to impose renewed restrictions on movement, while the uptake of remote working is also dampening demand for fuel.
"Consumption remains around 10.7 million barrels per day below 2019 levels due to the impact of virus containment measures on transport demand, the uptake of teleworking and the economic crisis unleashed by the virus," said the IEA.