Brent crude fell to an 11-day low on September 21, down 2.08% to $101.71 a barrel, as traders priced in the possibility of a meeting between US President Donald Trump and his Iranian counterpart, Masoud Pezeshkian, at the UN General Assembly this week.

Pezeshkian is currently en route to New York with top officials in what is expected to be his most high-profile visit to the US since entering power in 2024. 

Brent's retreat came despite Houthi missile and drone attacks on Riyadh and Saudi Aramco's Yanbu terminal, and reflects a recovery in Saudi loadings after the shutdown of the East-West pipeline on September 11.

Saudi exports rebounded to more than 4mn barrels a day in September from 2.4mn b/d in August, the lowest since 2013, as the kingdom rerouted cargoes through the Strait of Hormuz. Satellite tracking showed Saudi shipments through the strait averaging 2.9mn b/d, against 700,000 b/d in August.

West Texas Intermediate fell -2.59% to $97.69 a barrel, also the weakest since September 10, Newsbase data on September 21.

"It looks like some of the risk premium is coming out," said Tim Waterer, an analyst at KCM Trade, Reuters reported earlier. Trump said on September 20 he was open to meeting Pezeshkian, who arrives in New York this week.

Iran's security chief said Tehran had passed its conditions for negotiations to mediators, including a cessation of sanctions on Iran and a return of its frozen funds as well as the departure of US forces from the region.

Any de-escalation would raise the prospect of reopening the Strait of Hormuz, still closed to foreign shipping.

Middle East oil flows have been "surprisingly strong" despite the damage to Saudi infrastructure, JPMorgan said, putting regional flows at an average 17.1mn b/d over the past 10 days.

China has urged Iran to help rein in the Houthis following Saudi appeals, as the group gets closer to Aden, the last remaining major city controlled by the Saudi-backed Yemeni government in exile. 

Prices could reach $150 a barrel if the East-West pipeline is struck again, said Dmitry Kasatkin, a partner at Kasatkin Consulting, according to Russian media monitoring the situation.