Shipowners organisation Bimco has outlined new guidance for ships transiting the Strait of Hormuz following the seizure of two UK-flagged or operated ships by Iran on Friday.
Bimco said the US is "stimulating regional and international partners" to establish a naval operation to protect vessels operating in the region, code-named Operation Sentinel.
"The shipping industry is encouraged to support Operation Sentinel by following the guidance."
Bimco said it is vital that masters register with United Kingdom Maritime Trade Operations (UKMTO) when entering the Indian Ocean, and comply with flag state guidance.
UKMTO will also need between 24 and 48 hours notice of transit plans, including the expected times of entering and exiting Hormuz.
It will also need to be notified of navigation plans and any constraints or speed restrictions, plus the nationality of crew.
"In the event of any incident or being concerned, masters should call UKMTO immediately," Bimco added.
Captains have also been told to answer all VHF calls from coalition navies, and new channels will be offered as Channel 16 is becoming increasingly busy.
"Navies are operating in the Strait of Hormuz and to offer best protection they need to be aware of all vessel movements and intentions," Bimco said.