Backed by nearly 50,000 troops, warships and military aircraft, the United States on Wednesday resumed a naval blockade targeting merchant vessels transiting to and from Iranian ports.The US Central Command (CENTCOM), responsible for military operations in West Asia, said the blockade of maritime traffic entering and exiting Iranian ports began at 4 pm US Eastern Time on July 14 (1.30 am IST on July 15).Amid the crisis, oil prices rose with benchmark Brent crude climbing to around $81.54 a barrel by Tuesday night, its highest level since mid-June. Ship-tracking firm Kpler said vessel crossings through the Strait of Hormuz declined by about 52 per cent between July 10 and July 12 compared with the previous week.Meanwhile, in a post on X on Wednesday morning, the US Central Command said: “There are currently more than 20 US Navy warships and hundreds of military aircraft operating across the Middle East. American forces remain vigilant, lethal and ready.”On Tuesday, the US Central Command said that “more than 50,000 US service members are currently deployed across the Middle East”. The forces are stationed at 19 military bases US has in the countries across the region, in addition to personnel aboard nearly 20 US warships, it said.Announcing the blockade, Admiral Brad Cooper, the commander of the US Central Command, said, “Over the past seven days, Iran has intentionally targeted civilians across the region by attacking seven commercial ships, resulting in nearly a dozen civilian crew members being killed, missing or injured.”Admiral Cooper also accused Iran of launching dozens of missiles and drones towards neighbouring Gulf countries, adding that US forces were holding Tehran accountable for “unwarranted aggression that continues to endanger innocent lives.”On Tuesday, US President Donald Trump declared that the Strait of Hormuz was open to all commercial shipping except vessels linked to Iran.The renewed blockade comes after the US and Iran began exchanging missile and drone strikes on July 7, effectively ending the peace memorandum of understanding the two sides had signed on June 17.The US on Tuesday said it had launched a five-hour mission to strike military targets across Iran, including Bushehr, Chah Bahar, Jask, Konarak, Abu Musa and Bandar Abbas, to further degrade Iran’s ability to attack commercial shipping.In response, Iran’s Islamic Revolutionary Guard Corps (IRGC) said it had launched a broader retaliatory campaign against US allies and interests across the Gulf.