IRAN has reportedly test fired a ballistic missile amid escalating tensions with the US and UK in the Gulf. The Shahab-3 missile travelled 1,000km, but did not pose a threat to shipping or US bases, according to a Pentagon official. Iran is believed to have tested the medium-range missile in a bid to improve the “range and accuracy” of its weapons. News of the provocation emerged after Boris Johnson ordered the Royal Navy to accompany all British-flagged ships through the Strait of Hormuz. This ramping up of the navy’s protection mission by the new PM comes in the wake of Iran seizing Brit tanker the Stena Impero. It marks a dramatic escalation of the crisis with Iran following weeks of heightened tensions in the region. Iran possesses the largest and most diverse missile arsenal in the Middle East, according to the CSIS missile defence project. While Iran has not yet tested or deployed a missile capable of striking the US, it continues to hone longer-range missile technologies. The country has short and medium-range ballistic and cruise missiles capable of striking as far as Israel and southeast Europe. Iran has also become a centre for missile proliferation, supplying proxies such as Hezbollah and Syria’s al-Assad regime with a steady supply of missiles and rockets. According to the Military Balance, Iran has 32 batteries of Russian-made S-300 ground-to-air missiles that have been delivered by Moscow since 2016. They are seen as posing a serious threat. The Islamic Republic has also developed Iranian versions of these missile systems, including the Bavar 373, SAM Tabas and SAM Raad which are regularly displayed at military parades. The Revolutionary Guards claim that they shot down the US drone with a Khordad 3 missile, a version of the SAM Raad. IRAN’S nuclear capabilities have been the subject of concern and debate for more than two decades. Iran’s Supreme Leader Ayatollah Khamenei has repeatedly denied Iran is building a bomb and says weapons of mass destruction are forbidden under Islam. But its enrichment of uranium and history of deception created deep mistrust. After more than two years of negotiations and threats to bomb the country’s facilities, Iran and world powers agreed in 2015 to settle the dispute. The deal set limits on the Islamic Republic’s nuclear work in exchange for relief from economic sanctions that had crimped oil exports and hobbled its economy. Then in May 2018, Donald Trump announced the US was abandoning the pact negotiated under his predecessor and would reinstate sanctions. Little more than a year later, Iran responded by violating its limits on uranium enrichment. A think tank believes Tehran’s nuke scientists are ready to massively step up uranium enrichment at the heavily-fortified Fordow Plant.