A US Navy Commander has launched a scathing attack on Iran for its “offensive” and destabilising behaviour at sea. Vice Admiral James Malloy, who is in charge of the US Fifth Fleet, admitted he did not always know if the country was being deliberately provocative or just produced bad sailors. Speaking during a briefing to journalists, he expressed frustration at Iran’s activities in the Middle East, where it has repeatedly been accused of “harassing” the vessels of rival countries. He also warned he was entirely prepared to take “defensive but decisive” action in response to such activities, and cited an incident in 2017 in which a US ship had fired warning shots over an Iranian ship. “Their [Iran's] activities at sea are inherently destabilising because of how they react to other ships at sea,” he said. “If you come upon a ship of another nation there are certain things that you do to [reduce] risk; operate in such a way that is safe, anticipated. “Things you don’t do: you don’t cross bow of another ship when it’s manoeuvring; you don’t drive close proximity to another ship when it’s manoeuvring. “Collectively we see this as threatening behaviour, and for the US that means I remain prudent and cautious when I’m operating in the vicinity of the Iranians because I don’t know whether it’s just poor seamanship or it’s an intent to harass. “But either one is unsafe and we are prepared to defend against them.” Vice Admiral Malloy went on to criticise the threatening rhetoric coming out of Tehran and said he suspected the regime of prolonging the conflict in Yemen by continuing to smuggle weapons into the country. He also confirmed that while the US had seen a decrease in provocative behaviour from the Iranians over recent months, he did not understand why. The commander, who is in charge of a 33-nation coalition, the Combined Maritime Forces (CMF), which includes the UAE, contrasted Iran with the “professional” navies belonging to GCC countries. He cited Oman as a leading example in the region for professional seamanship, while also praising the UAE Navy, which has led taskforces twice as part its role with the CMF. “They [the UAE] are a very capable blue-water Navy,” he added. “I think since 2001, the capabilities of the GCC partners have grown in leaps and bounds.” Earlier this week, the Vice Admiral raised concerns about the increasing capabilities of Iran’s navy. The country has improved weapons systems and can deploy unmanned explosive boats designed to target enemy vessels, he said. <strong>___________</strong> <strong>___________</strong> The US has also accused Iran of supplying Houthi rebels in Yemen with similar technology. In 2015 and 2016, coalition forces intercepted four weapons shipments including AK-47s, RPGs and artillery rounds bound from Iran to Yemen, he said. “I’m not going to tell you, and I certainly don’t believe, that 2015 and 2016 was an outlier, or that I have closed that [off] all together,” he said. “My assumption is I’m not done yet, there’s still things going into Yemen that I need to stop. “There is nothing good happening from the arms that are being illegally shipped into Yemen. “It is destabilising - it delays peace there. It exacerbates the disastrous humanitarian crisis we’re facing in Yemen and delays humanitarian efforts coming in, which we fully support. “We see the world trying to end this thing and one group doing nothing to end it, and probably the opposite.” In 2017, the USS Thunderbolt fired warning shots across the bow of an Iranian vessel after it drove at the patrol ship at speed and then ignored internationally-recognised signs to desist. It pulled away after the warning shots were fired, just moments before the US command took “decisive” action, Vice Admiral Malloy said. <strong>___________</strong> <strong>Idex 2019 highlights: Meet Titan</strong> <strong>___________</strong> President Trump, in the middle of last year, shared naval statistics showing no instances of Iranian harassment at sea in the first half of 2018, compared to 22 in 2016, 36 in 2016, and 14 in 2017. “We have had less instances of [Iranian harassment] over time, but whether that is because we have had less opportunity for those interactions, or whether it’s a conscious decision from the perspective of Iran to start acting professionally, I don’t know,” the Vice Admiral said. “Their activities, combined with the rhetoric that they pronounce - ‘We will close the Gulf, we will close the straits’ - and the exercises that they engage in are inherently offensive in nature.”