In Bahrain, at another military base well out of the public eye and set apart from that country's simmering unrest, Royal Navy personnel man the naval HQ known as the UK Maritime Component Command (UKMCC), directing Britain's minesweepers and frigates around the Gulf, in co-ordination with the far larger US Navy 5th Fleet headquarters.

BBC: 'East of Suez': Are UK forces returning?

Earlier, a spokesman for the US Navy's 5th Fleet, Lt Nathan Christensen, said the USS Howard was within 8km (5 miles) of the Ukrainian vessel, but refused to say whether they were preparing to attack the pirates.

BBC: Warships surround Somali pirates