Tankers in the Red Sea have begun loading oil from a critical Saudi Arabian pipeline that was shut down this month after it was damaged in an attack. A total of nine tankers on the Red Sea coast have loaded about 12.5 million barrels of crude since Sunday, according to satellite imagery analyzed by Kpler, a maritime data firm. Three of those tankers were loaded in just the last 24 hours, the strongest indication yet that the East-West pipeline, a 750-mile network that transports crude across Saudi Arabia, was at least partly working again. The Saudi authorities said on Sept. 11 that they had taken the pipeline offline, blaming a drone attack by an Iranian-backed Iraqi militia.

"The pipeline has resumed," said Amena Bakr, head of Middle East & OPEC+ Insights at Kpler. Neither Saudi Arabia’s energy ministry nor Saudi Aramco, the state oil giant, has made any public statement on the pipeline since it was attacked, and each declined to comment on the resumption of operations. An extended closure of the East-West pipeline threatened to drastically reduce how much oil Saudi Arabia, the region’s largest oil exporter, could get out of the region. The pipeline became the Saudis’ main workaround when the war in Iran effectively shut the Strait of Hormuz seven months ago.

Saudi Arabia has restored flows to about 3.5 million barrels per day, according to two people with knowledge of the pipeline repairs who were not authorized to speak publicly. While getting back to full capacity could still take weeks, analysts said the repairs had proceeded quickly. "The ability to keep the flows going is integral to the Saudi economy," said Colby Connelly, head of Middle East content at Energy Intelligence, a research firm. "Their ability to show their buyers that they can continue to be a reliable supplier, even in the face of these very extreme circumstances, is extremely important to them."