Singapore — Oil prices fell on Thursday as record US output and rising crude stockpiles dampened the impact on markets of tighter US sanctions on Iran and oil cartel Opec’s continued curbs on supply.

Brent crude futures were at $74.35 a barrel at 12.37am GMT, down 22c, or 0.3%, from their last close. US West Texas Intermediate (WTI) crude futures were at $65.60 a barrel, down 29c, or 0.4%, from their previous settlement.

Crude futures rose to 2019 highs earlier in the week after the US said on Monday it would end all exemptions for sanctions against Iran, demanding countries halt oil imports from Tehran from May or face punitive action from Washington.

“Following the US decision to toughen its sanctions on Iran ... we have revised up our end-year forecast for Brent crude from $50 to $60 a barrel,” analysts at Capital Economics said in a note.

The US decision to try and bring down Iran oil exports to zero comes amid supply cuts led by Opec since the start of the year, aimed at propping up prices. As a result, Brent crude oil prices have risen by almost 40% since January.

Despite this, Capital Economics said “we still expect oil prices to fall this year as sluggish global growth weighs on oil demand, US shale output grows strongly, and investor aversion to risk assets such as commodities increases”.

US crude oil production has risen by more than 2-million barrels per day (bpd) since early 2018 to a record of 12.2-million bpd currently, making the US the world’s biggest oil producer ahead of Russia and Saudi Arabia.

In part because of soaring domestic production, US commercial crude oil inventories last week hit an October 2017 high of 460.63-million barrels, the Energy Information Administration (EIA) said on Wednesday. This was a rise of 5.5-million barrels.