Ukraine has built and tested a low-cost alternative to US Patriot missiles, potentially reducing a shortfall in anti-air interceptor weapons.

Patriots cost more than $4 million each and take around two years to build; the Iran war has depleted US stockpiles so far that they will take at least three years to replenish.

But overseas orders are at record-high levels: Lockheed Martin aims to triple production but does not expect to do so until 2030. Ukraine’s version costs $700,000, and uses infrared rather than ground-based radar — a less precise, but cheaper, guidance system.

Russian ballistic missile attacks are “the gift and the curse” for Ukraine, a defense analyst said, giving it plenty of testing opportunities for its surface-to-air weaponry.