President Barack Obama on Thursday urged North Korea to engage with the international community over its nuclear programme or risk making the lives of its people even harsher.
"North Korea's continued pursuit of nuclear weapons will only lead to more isolation and less security. But there is another path available to North Korea," Obama told U.S. troops in South Korea in a Veterans Day ceremony to commemorate the Korean War.
Speaking at a U.S. base about 60 miles south of the demilitarized zone dividing North and South Korea, Obama said Pyongyang's nuclear weapons programme, and the sinking of a South Korean naval, mark a "path of confrontation and provocation."
"In the wake of this aggression, Pyongyang should not be mistaken: the United States will never waver in our commitment to the security of the Republic of Korea," he said.
Tension on the peninsula has been high after Washington and Seoul blamed North Korea for the March sinking of a South Korean corvette, the Cheonan, which killed 46 sailors.
The United States is one of five regional powers, along with Russia, China, Japan, South Korea, involved in stalled six-party talks on dismantling Pyongyang's nuclear arms programme.
"If they choose to fulfill their international obligations and commitments to the international community, they will have the chance to offer their people lives of growing opportunity instead of crushing poverty," Obama told a cheering crowd of 1,400 troops packed into a gymnasium.
The president is likely to discuss North Korea during meetings with South Korean President Lee Myung-bak and Chinese President Hu Jintao that he will hold on Thursday on the sidelines of a Group of 20 summit.
The event comes a few weeks after the 60th anniversary of the outbreak of the Korean War, which began when North Korea invaded the South, the legacy of which sees 28,500 U.S. troops still stationed in South Korea.
"Because the Korean War ended where it began geographically, some used the phrase 'Die for a Tie' to describe the sacrifice of those who fought here," Obama said. "This was no tie. This was a victory. It was a victory then, and it is a victory today."