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The UK government has said it will provide a Royal Navy escort for British-flagged ships passing through the Strait of Hormuz - amid increasing diplomatic tensions in the Gulf.
Ship owners are being advised to give details of their route so they can be escorted by the frigate HMS Montrose.
The move follows the seizure of the British-flagged tanker Stena Impero by Iran's Revolutionary Guard on Friday.
The ship's owner said the crew are safe and co-operating with officials.