President Yoon Suk Yeol oversaw the largest joint live-fire exercises ever conducted by the South Korean and US military, as the two allies marked the last day of their three-week drills Thursday meant to openly deter North Korea’s growing aggression.

The show of force, which took place at Asia’s largest military training field in Pocheon, Gyeonggi Province, involved mobilizing the South Korean F-35A fighter jets and K9 howitzers and the US F-16 jets and Gray Eagle drones. About 2,500 Korean and American soldiers participated in the event. Similar drills took place six years ago.

“Real peace comes from not relying on the goodwill of enemies, but projecting our power on our own,” Yoon said in a speech before the drills started. South Korean and American security and defense officials, alongside Korean lawmakers as well as ordinary Koreans, watched the military maneuvers.

Thursday’s drills, designed to demonstrate how the two allies would respond to Pyongyang’s attacks, are the latest highlight of a push by the Yoon administration to deliver on ushering in peace in the divided peninsula through “overwhelming strength” -- a pledge the conservative leader announced in May last year when he took office. The North still defies sanctions prompted by its nuclear buildup.

Since then, the South Korean leader has built on closer ties with not only the US but Japan, a partner in a three-way, US led coalition that has been working on denuclearizing North Korea.

In late April, Seoul and Washington signed a pact giving the South a bigger say in a potential US nuclear response to the North’s attacks. Yoon, who touts the agreement as an upgrade to the 70-year-old security ties, shook hands on tighter relations with his Japanese counterpart at their back-to-back summits that ended in May.

Yoon’s national security adviser was in Japan on Wednesday and Thursday to meet with his US and Japanese counterparts to chiefly discuss policy on North Korea. Cho Tae-yong, the security chief, has openly warned of a stern response to Pyongyang’s so-called military satellite launch, a test that some believe is a cover to advance its ballistic missile technology.

Dismissing such protests, the North has said it will back a second launch as part of its self-defense, having called the failed initial test two weeks ago an effort to more closely monitor US military activities. Pyongyang says Washington should ease sanctions and drop its “anti-North Korea policy” for the regime to return to nuclear negotiations. The US has rejected the demand.