Brent crude oil futures slid for a second session on Monday as the market was weighed down by a climb in US output to a record-high and expectations that Opec members will raise supplies.
Oil prices fell for a second day on Tuesday, driven by ongoing evidence of rising US crude output, while wary investors sold off stocks, bonds and commodities.
Oil rose more than 1% on Tuesday with benchmark Brent crude above $70 a barrel for the first time in a week on Tuesday, boosted by healthy world economic growth prospects and expectations for continued production curbs.
Brent crude oil prices held near $70 a barrel on Tuesday, a level not seen since 2014's dramatic market slump.
The Organisation of the Petroleum Exporting Countries and allies including Russia are keeping supply limits in place in 2018, a second year of restraint, to reduce a price-denting glut of oil held in inventories.
Six days of anti-government protests in Opec's third-largest producer have added a geopolitical risk premium to oil prices, though Iran's production and exports have not been affected.
Oil prices fell on Wednesday after hitting a near two-and-a-half year high in the previous session as analysts said the rally was gradually running out of steam despite supply outages in Libya and the North Sea.