Goldman Sachs lowered its year-on-year oil demand forecast for 2019 citing disappointing global economic activity, which was further weighed down by milder weather, fuel power demand destruction and historical downward revisions, suggesting lower oil demand growth in 2018.

The bank revised down its 2019 oil demand growth forecast to 1.275 million barrels per day (mb/d), from 1.45 mb/d at the beginning of the year. However, this is still above the consensus estimates at about 1.05 mb/d for 2019, bank added.

"All else constant, we estimate that an upward revision of consensus 2019 oil demand growth expectations to our 1.275 mb/d forecast would rally Brent prices by $6 per barrel," it said.

Goldman forecast 2020 oil demand growth at 1.45 mb/d on a gradual acceleration in global economic growth as well as a demand boost from International Maritime Organization's new fuel rules for ships from the start of 2020.