A clandestine Israeli nuclear compound at the center of the country’s undeclared nuclear weapons program is undergoing what appears to be its largest construction project in decades, satellite images analyzed by the AP demonstrate.

A deep ‘soccer field’

A dig roughly the size of a soccer field and probably a few stories underground now sits a mere yards from the waning reactor at the Shimon Peres Negev Nuclear Research Center just outside the southern city of Dimona. The compound is the headquarters of decades-old secret laboratories that reprocess the reactor’s spent rods to obtain weapons-grade plutonium for the Jewish State’s atomic weapons program.

The construction’s purpose, however, is unclear. Israel maintains a longstanding policy of nuclear ambiguity, This means that Jerusalem neither confirms nor denies having nuclear weapons capabilities. Israel is one of only four countries that have yet to join the Non-Proliferation Treaty, an international accord whose aim is to stem the proliferation of nuclear weapons.

The construction comes as Prime Minister Benjamin Netanyahu made several thinly veiled threats against Iran for their nuclear ambitions. Israel365 News reported on Thursday that Netanyahu called on Iran to consider the holiday of Purim as a cautionary tale should Iran go ahead and target Israel with nuclear weapons.

The background

With assistance from France, Israel secretly built its nuclear facility in the late 1950s in the southern Negev desert near te town of Dimona. Jerusalem concealed the military purpose of the compound from America for years, even referring to the site as a ‘textile factory.’

Israel is widely believed to be one of just nine nuclear-armed nations worldwide. Given the secrecy of its program, it is still not clear how many weapons it owns in its possession. Analysts estimate that Dimona possesses material for at least 80 weapons. Those bombs probably could be launched via fighter jets, land-based ballistic missiles, or submarines.

For decades, Dimona’s facility layout has remained unchanged. But, last week, the International Panel on Fissile Materials at Princeton University claimed that they witnessed “significant new construction” at the facility via commercial satellite images.

Sizes of the holes

The images show that southwest of the facility, a hole roughly 1,165 yards long and 65 yards wide has been dug. A trench measuring at approximately 360 yards runs adjacent to the dig.

Roughly 1.25 miles west of the facility, boxes are stacked inside 2 rectangular holes that seem to feature concrete bases. These types of concrete pads are usually used to embalm nuclear waste.

Other images from Planet Labs imply that the construction adjacent to the nuclear facility started in early 2019 and has progressed slowly since.

Experts weigh in

Analysts told the AP that the reactor’s heavy-water reactor has been active since the 1960s, which is much longer than most reactors from the same time period. That can affect both safety and effectiveness.

Analysts claim that these types of safety concerns could compel Jerusalem to decommission or retrofit the reactor.

“I believe that the Israeli government is concerned to preserve and maintain the nation’s current nuclear capabilities,” said Avner Cohen, a professor of nonproliferation studies at the Middlebury Institute of International Studies at Monterey, who has written extensively on Dimona.

“If indeed the Dimona reactor is getting closer to decommissioned, as I believe it is, one would expect Israel to make sure that certain functions of the reactor, which are still indispensable, will be fully replaced.”

Valerie Lincy, executive director of the Washington-based Wisconsin Project on Nuclear Arms Control hinted that the latest evidence of expansion may have been leaked intentionally explaining that Israel has the capability of preventing satellite images from recording its activity in the Nuclear site.

“I think the most puzzling thing is … you have a country that is very aware of the power of satellite imagery and particularly the way proliferation targets are monitored using that imagery,” Lincy said. “In Israel, you have one known nuclear target for monitoring, which is the Dimona reactor. So you would think that anything that they wanted to keep under the radar would be kept under the radar.”

If it was leaked intentionally, the message could be a direct threat to Iran’s atomic ambitions.