Saudi Arabia appears to be expanding its ballistic missile factory to produce larger solid fuel missiles capable of flying farther or carrying heavier payloads, according to two U.S. researchers. Their findings draw on more than a year of commercial satellite imagery.

Sam Lair and Michael Duitsman of the Foreign Policy Research Institute examined Planet Labs images of the al-Duwadimi complex, located about 125 miles west of Riyadh. The U.S. satellite company captured the images between April 2025 and September 2026.

The researchers assessed that one new building contains casting pits, which are wells used to pour mixed fuel ingredients into missile motor casings so the material can harden. The building is at least twice as large as the structure believed to contain the complex’s existing casting pits.

Walls that appear intended to protect nearby structures from accidental explosions flank the new building. Lair and Duitsman said a second new building could store either fuel ingredients or completed missile components.

The imagery “suggests that Saudi Arabia is expanding the infrastructure at the missile production complex, likely to produce larger missiles which could deliver larger payloads or reach longer ranges,” the researchers wrote. The Saudi embassy and Information Ministry did not respond to requests for comment.

Militaries favor solid fuel missiles because they can remain stored for extended periods and launch faster than liquid fuel systems. More capable weapons could improve Saudi Arabia’s ability to deter Iran, strengthen its military self reliance and affect its conflict with Yemen’s Houthi fighters, who are backed by Tehran.

Experts from the Foreign Policy Research Institute, the International Institute for Strategic Studies and CNA said the composition of Saudi Arabia’s missile force suggests the al-Duwadimi complex depends on Chinese technology. Lair and Duitsman also found characteristics resembling Chinese missile factories.

Saudi Arabia secretly obtained about 40 liquid fuel DF-3 ballistic missiles from China in 1987, according to a declassified 1991 CIA estimate. The kingdom displayed two of those missiles publicly for the first time during an April 2014 military parade.

The institute’s team also identified wreckage in Yemen from social media photographs and videos that it assessed came from a Chinese designed DF-15 missile fired by Saudi Arabia. Lair said the kingdom may now be manufacturing the solid fuel DF-15.

Lair also said the expansion was likely intended to support production of the longer range DF-21 or a similar missile. Riyadh is believed to have sought Chinese assistance because Washington has long restricted exports of missile systems with longer ranges.

The Chinese embassy and defense ministry did not respond to requests for comment, while the CIA declined to comment. The White House also did not respond to a request for comment.

Sascha Bruchmann, a research fellow at the International Institute for Strategic Studies, said longer range missiles would let Saudi Arabia strike Iran without exposing its U.S. supplied F-15 fighters to Iranian air defenses. He agreed that the expansion could support production of more powerful solid fuel missiles.

“You’d want a system to threaten whatever is holy to Tehran … if you don’t have the political will to send an F-15 with JDAMs over Tehran,” Bruchmann said. “Iran has a lead because its missiles and drones can strike Saudi wherever it wants. The Saudis could close that capability gap a bit.”

Janes, a defense intelligence company, separately reviewed the analysis and said the buildings “may suggest an effort to expand production capability or support the development of longer-range missiles.” CNA analyst Decker Eveleth said other Gulf powers are likewise expanding offensive and defensive arsenals.

The expansion also could strengthen bipartisan congressional opposition to an agreement under which the U.S. would help Riyadh establish uranium enrichment for power generation. Opponents argue the agreement lacks sufficient safeguards against a secret Saudi nuclear weapons program, an intention the kingdom denies.

The satellite record shows work beginning in April 2025 with clearing and excavation for the suspected storage building. Construction on the suspected casting pit structure started later that month or in early May, according to the assessment.

A December 12, 2025, image showed what researchers assessed were two deep pits inside the still roofless building. A Sept. 18, 2026, image showed part of the roof still missing, along with “heavy duty blast diverting walls” designed to shield adjacent structures from accidental explosions.

Researchers said those walls somewhat resemble features visible in imagery of U.S. and Iranian missile plants. They called the barriers “further evidence the building is for casting solid propellant motors.”

The institute said completing the roofs would not take long, although installing casting equipment could require several months. The facility could be prepared to begin missile production as early as the end of the year.