The first of two vessels carrying 1,000 tons of a Chinese-made chemical that could be a key component in fuel for Iran’s military missile program has anchored outside the Iranian port of Bandar Abbas on Thursday, ship tracking data shows. It could be a signal that Iran’s missile production is back to business as usual after the devastating, and embarrassing, attacks by Israel on key factories last year.

The ship, Golbon, left the Chinese port of Taicang three weeks ago loaded with most of a 1,000-ton shipment of sodium perchlorate, the main precursor in the production of the solid propellant that powers Iran’s mid-range conventional missiles, according to two European intelligence sources.

The sodium perchlorate could allow for the production of sufficient propellant for some 260 solid rocket motors for Iran’s Kheibar Shekan missiles or 200 of the Haj Qasem ballistic missiles, according to the intelligence sources.

The shipment comes as Iran has suffered a series of regional setbacks with the collective defeat suffered by its allies: the fall of Bashar al-Assad in Syria and Hezbollah’s losses in Lebanon. Following Israel’s strike on Iran’s missile production facilities in October, some Western experts believed it could take at least a year before Iran could resume solid-propellant production. This delivery points to Iran being not far from – or that they could already be back to – the production of its missiles.