UK's amphibious light infantry force Royal Marines have started training sessions at the Selo Training Area in Bulgaria, as part of the Platinum Lion 15-3 exercise.
The training also included members from the US Marines 2nd Battalion, 8th Marine Regiment, Black Sea Rotational Force (BSRF), and the Bulgarian Armed Forces.
As part of the exercise, participants are being trained in cordon and search operations, intelligence gathering, live-firing, as well as tactical manoeuvres.
Royal Marines commando lieutenant Thomas Barry said: "Seeing how the US Marines operate their fire support systems was interesting, as well as the different weapons systems used, rates of fire and the means of implementing them; it was great to work through.
"The US Marine Corps led this exercise, but I look forward to the UK stepping up its role in the next one."
Platinum Lion 15-3 is designed to strengthen the partnership between Nato nations to combat security threats.
During a live-fire attack, the Royal Marines performed the actual assault, a Romanian Air Force aircraft provided air support, while the US Marines provided fire support with machine guns.
BSRF 2nd Battalion, 8th Marines Golf Company commanding officer captain Michael R McNicoll said: "Platinum Lion 15-3 was designed to promote regional cooperation and foster interoperability between our nations in order to combat security threats.
"We have done this through realistic training where we shared our ideas, thoughts, techniques, tactics and procedures."
Image: The Platinum Lion 15-3 exercise includes Royal Marines, the US Marines from 2nd Battalion, 8th Marine Regiment, Black Sea Rotational Force (BSRF) and the Bulgarian Armed Forces. Photo: courtesy of Royal Navy.