UK submarine HMS Tireless has returned to Gibraltar after being withdrawn from the search for the missing Malaysian plane in the Indian Ocean.
Last week, the submarine, which is equipped with specialist sonar capabilities, was withdrawn from the hunt for flight MH370 along with Royal Navy survey ship HMS Echo.
HMS Tireless has been undergoing minor repairs while docked in Gibraltar following its return.
Flight MH370 disappeared on March 8, with 239 passengers on board. The incident triggered an international search operation that has yet to find the plane.
Australian authorities have concluded that there is no prospect of further acoustic detection of the black box.
UK Defence Secretary Philip Hammond said: “The search for the black-box signal has been an extremely challenging operation and, while we all hoped for a faster and more conclusive result, I am very proud of the contribution British forces have been able to make.
“The operation is now moving into a new phase, requiring different capabilities.”