South Korea and the United States wrapped up a massive combined exercise Sunday after their weeklong maneuvers.

The two sides kicked off the Ssangyong, or Twin Dragon, drills last Sunday near Pohang, North Gyeongsang Province, as part of the annual Foal Eagle field training between the allies.

South Korea said the combined exercise ended earlier in the day as scheduled and the US forces that joined the exercise will return to their bases, for instance in Okinawa, Japan.

Among the US assets mobilized for this exercise were the USS Wasp, a 40,500-ton multipurpose amphibious assault ship, and the USS Bonhomme Richard, another vessel of the same class. Wasp was carrying several F-35B stealth fighter jets capable of vertical take-off and landing.

For the combined exercise, South Korea and US originally planned to mobilize their naval and marine forces to stage the so-called D-Day landing operation, reminiscent of the Invasion of Normandy, on a beach of the southern coastal city of Pohang on Thursday. The operation, however, was cancelled due to adverse weather.

The number of participating troops hasn't been announced. The Ssangyong practice is held annually, but it is conducted on a larger scale every two years, involving more than 10,000 American marines, mostly based in Okinawa, and thousands of South Korean marines.

Ssangyong is designed to build and maintain fundamental military readiness throughout the alliance, according to the Combined Forces Command.

South Korean military said CFC chief Gen. Vincent K. Brooks and South Korean Marine Corps Commandant Lt. Gen. Jun Jin-goo both inspected the exercise on Thursday and encouraged the troops.

This year's exercise didn't allow media coverage, apparently mindful of a nascent mood for peace on the Korean Peninsula.

Meanwhile, South Korea and the US plan to hold the Key Resolve command post exercise for two weeks starting April 23.(Yonhap)