Iran unveils new 'biggest' drone
Iran says it has developed a drone with a range of 2,000km (1,200 miles), which would enable it to cover much of the Middle East, including Israel.
The Islamic Republic's Defence Minister said the unmanned aircraft could carry out reconnaissance missions or launch missile strikes.
Hossein Dehghan said sanctions imposed by "enemies" would not stop progress.
Iran's claims of developments in defence technologies cannot be independently verified.
Iran's programme underscores the fact that drone technology is proliferating rapidly.
Once largely the preserve of the US and Israel, UAVs are now spreading around the world.
However drones have largely been used in clear skies against enemies with limited air defences.
When fighting broke out between Georgia and Russian forces in 2008 Georgia's Israeli-supplied drones were quickly shot out of the sky, suggesting a rather more cautious assessment is needed concerning the long-term utility of such systems.
Tehran said the new drone, called the Fotros, was its biggest yet and was capable of being airborne for up to 30 hours.
While the US use of drones for intelligence gathering and missile strikes as part of its war on terror has been widely reported, many other countries - including China - now have unmanned aerial vehicles (UAVs).
The BBC's diplomatic correspondent, Jonathan Marcus, says Iran is eager to play up its defence capabilities for propaganda reasons - but may not possess the sorts of sophisticated intelligence capabilities needed to direct UAVs to their targets.
Sanctions have been imposed on Iran because of its failure to halt uranium enrichment.
Western nations fear the country is developing a nuclear weapons programme; Iran maintains that its nuclear research is purely for peaceful purposes.