Oil analysts cut their price forecasts for 2018 for the first time in almost a year in August, given growing concern over the impact on crude demand from escalating trade tensions, although falling supply, particularly from Iran, would likely limit losses, a Reuters poll showed on Friday.

A crude oil terminal under construction is pictured off Ningbo Zhoushan port in Zhejiang province, China January 6, 2018. Picture taken January 6, 2018. REUTERS/Stringer

A survey of 45 economists and analysts forecast Brent crude to average $72.71 a barrel in 2018, 16 cents lower than the $72.87 projected in the previous month’s poll and above the $71.96 average so far this year. The price was forecast to average $72.58 in 2019.

U.S. crude futures were forecast to average $67.13 a barrel in 2018, compared with $67.32 forecast last month and an average of $66.40 until now.

“The eventual loss of Iranian barrels is likely to match, if not exceed, the amount seen during the multi-lateral round of sanctions in 2012-2015,” said Harry Tchilinguirian, global head of commodity market strategy at BNP Paribas. Supply is also at risk in countries like Venezuela, Libya and Angola, he said.

“These supply side factors presents strong upside for oil prices.”

U.S. sanctions on Iran’s energy sector will come into force on Nov. 4, although the country’s crude oil and condensate exports are already expected to have fallen to a 16-month low in August.

The United States wants to force buyers of Iranian oil to cut their imports from OPEC’s third-largest producer to nothing, after an international nuclear deal between the two nations was dissolved.

However, there is a concern among analysts that global trade disputes could undermine economic growth, which in turn may mean Asian importers’ demand for crude oil declines.

The United States is embroiled in an ever-escalating trade war with multiple countries, especially China.

“Trade tensions could slow oil demand growth in Asia, likewise possible contagion of the Turkey crisis; slower demand growth would make it easier to replace Iranian barrels,” said Carsten Fritsch, senior commodities analyst at Commerzbank.

Analysts said the Organization of the Petroleum Exporting Countries (OPEC) would continue to adjust its crude supply to ensure the global oil market remained in balance.

Saudi Arabia will be a strong contender to fill in the supply deficit caused by Iran sanctions and tensions elsewhere in the coming months, a majority of industry experts said.

“At the moment the market is looking balanced over the fourth-quarter, assuming Iranian supply falls by around 500,000 barrels per day. The obvious upside risk is if Iranian losses are greater than this, as this would push the market into deficit over the final quarter,” said ING commodities strategist Warren Patterson.