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”.
Source: https://www.bbc.com/news/articles/c5yv6xr6me3o?at_medium=RSS&at_campaign=rss