Prince William is to join Royal Navy patrols searching for drug runners in Caribbean waters.

It will be one of the roles he is expected to take on during his two-month secondment on the frigate HMS Iron Duke, which begins on Monday.

The aim is for William, 25, to learn about the Navy's ethos and capabilities as he prepares for his future role as head of the armed forces.

Rear Admiral Robert Cooling, Assistant Chief of Naval Staff, said the attachment would be rigorous and challenging but spoke with pride about Sub-Lieutenant Wales joining HMS Iron Duke.

The senior officer joked: "It will be a real thrill and privilege - not a pain in the ass - for the ship's company.

"If we treated him like some super VIP and tailored a programme for him and walked around on egg shells, then that would be difficult. But he's not, he's going to come just like any other young officer and do all the things that young officers get involved in."

Sub-Lieutenant Wales is following in the footsteps of his father, the Prince of Wales, uncle the Duke of York, and grandfather the Duke of Edinburgh, who all served in the Royal Navy.

The Prince - an officer in the Household Cavalry's Blues and Royals - will spend a number of weeks learning basic skills such as navigation, boat handling and sea safety.

He will also briefly tour various units such as the Royal Marines and Air Fleet Arm, where he will have a chance to fly its helicopters.

But the Royal Navy is expected to keep a tight control on William's flying operations after the Prince was criticised for piloting a Chinook to social events while on secondment to the RAF earlier this year.

Rear Admiral Cooling said the frigate was chosen to host William's time at sea after "operational security considerations" but mainly because it offered the Prince the "best grounding" in naval activities as other warships in the Gulf were in "operational stand down" or transit.

Iron Duke's crew will be involved with operations to catch drug runners which have seen British vessels seize around 20 tonnes of cocaine in the north Atlantic in the past 18 months.

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