The 300ft catamaran is due to leave for the Arctic Circle early next week
Portsmouth is currently playing host to one of the US Navy’s latest warships.
The enormous 300ft HSV2 Swift catamaran arrived on Monday to prepare to a military exercise in the Arctic Circle.
During the training exercise, Swift will be home to 60 Royal Navy personnel, comprising staff from the Mine Countermeasures Squadron, divers from Fleet Diving Unit 02 and engineers from Fleet Support Unit 01.
Commander Peter Williams, in charge of the mine countermeasures force, said: “Swift’s arrival in Portsmouth demonstrates the close links between the Royal Navy and the United States.
“Her high speed of up to 50 knots and ability to provide engineering and stores support at sea without needing to go alongside offers tremendous flexibility to the way we will operate.”
Swift is set to leave Portsmouth for Norway on 20 February.