Two of the Royal Navy's Offshore Patrol Vessels have left Falmouth docks for a five-year deployment to the Indo-Pacific.
HMS Tamar and HMS Spey will act as the Royal Navy's eyes and ears, working with Britain's allies to tackle drug-running, smuggling, terrorism and other illegal activities.
It comes as China continues to expand its military presence in the disputed South China Sea, increasing tension with its neighbours.
It is hoped that the presence of the two patrol vessels might improve relationships with allies in the region.
The ships will also take part in exercises with other navies and Armed Forces, with their patrol area stretching across both the Indian and Pacific oceans - extending as far north as the Bering Sea and as far south as Tasmania and New Zealand.
They will arrive in the Pacific on the back of the maiden deployment by HMS Queen Elizabeth and her Carrier Strike Group.
No permanent home has been assigned to the pair - instead they will use Pacific bases and ports which best meet their needs and mission.
The ships started their journey to the Indo-Pacific earlier this week after setting sail from Portsmouth.