What is a naval blockade and how would it work in Strait of Hormuz?

ShareSaveAdd as preferred on GoogleGeorge WrightandRachel Clun,business reporterAFP via Getty ImagesA US military blockade of maritime traffic entering and leaving Iranian ports began at 14:00 GMT (15:00 BST) on Monday. The US says ships coming or going from elsewhere would be allowed to pass through the Strait of Hormuz, a critical waterway Iran effectively closed in response to US-Israeli strikes. It comes after negotiators from both sides failed to reach a deal to end the war, which began on 28 February but is currently under a two-week truce. US President Donald Trump has said direct talks with Iran in Pakistan failed because Iran was unwilling to give up its nuclear ambitions - but a US official said there had been a much longer list of disagreements, including on Iran's control of the strait. Here's what we know about the US announcement. Trump wrote on social media on Sunday that the US was going to start BLOCKADING any and all Ships trying to enter, or leave, the Strait of Hormuz . I have also instructed our Navy to seek and interdict every vessel in International Waters that has paid a toll to Iran. No one who pays an illegal toll will have safe passage on the high seas, he said. He added that the US will also begin destroying the mines he said Iran has laid in the strait. Any Iranian who fires at us, or at peaceful vessels, will be BLOWN TO HELL! he continued. Trump said that at some point an agreement on free passage will be reached, but Iran has not allowed that to happen by merely saying, 'There may be a mine out there somewhere,' that nobody knows about but them . He added in another post that Iran promised to open the Strait of Hormuz, and they knowingly failed to do so . As they promised, they better begin the process of getting this INTERNATIONAL WATERWAY OPEN AND FAST! he said. Trump says Iran still wants a nuclear weaponHow could the blockade work in practice?The US Navy Commander's handbook on naval operations law from 2022 defines a blockade as a belligerent operation to prevent vessels and/or aircraft of all states, enemy and neutral, from entering or exiting specified ports, airfields, or coastal areas belonging to, occupied by, or under the control of an enemy state . Trump initially said the US Navy would begin the process of blockading the strait effective immediately . The US Central Command (Centcom) later said its forces would begin implementing the blockade at 10:00 EDT (14:00 GMT) on Monday. A note sent by Centcom to mariners, seen by the BBC, says the blockade will encompass the entirety of the Iranian coastline to include but not limited to ports and oil terminals, and applies to all vessel traffic, regardless of flag. It said neutral vessels are being granted a grace period to depart Iranian ports that will expire once the blockade begins, after which time any vessel entering or departing the blockaded area without authorisation is subject to interception, diversion, and capture . Centcom