While talks continue between the US and Iran, Sky News’ Data and Forensics team has been analysing Iran’s preparations for potential strikes.

Satellite images analysed by Sky News’ Data and Forensics team show Iran has fortified its nuclear and defence facilities, alongside conducting live drills with Russian forces amid rising tensions with the US military.

What we know about activity at Iran’s nuclear facilities

Iran appears to be fortifying defences at its nuclear plants and military facilities since strikes by Israel and the US in June 2025 damaged infrastructure at three key sites. Core enrichment activity remains constrained and under close international scrutiny.

The main sites affected by last year’s strikes were Fordow Fuel Enrichment Plant, Natanz enrichment facility and Isfahan Nuclear Fuel Complex. They are key to Iran’s core nuclear infrastructure.

The Isfahan Complex is in central Iran, 135 miles south of Tehran, near the city of Natanz. It is central to the nuclear fuel cycle, converting uranium into forms suitable for enrichment.

Isfahan includes an underground area where diplomats say much of Iran’s enriched uranium has been stored. Iran’s authorities have always said they are not trying to develop nuclear weapons.

Satellite images from 6 December 2025 to 24 January 2026 show structural repair and new efforts to bury tunnel entrances to the site.

Read More: How Iran might be preparing itself for a potential US strike