President Obama said Friday in Seoul that Washington stands "shoulder to shoulder" with South Korea in its rejection of a nuclearized North Korea and that it may be time to consider more sanctions against the isolated state.
Addressing a joint news conference alongside South Korean President Park Geun-hye, Obama said threats by North Korea will get it "nothing except further isolation" from the global community.
He conceded that additional sanctions may have limited impact. "We are not going to find a magic bullet that solves this problem overnight," Obama said.
"We can't waver in our intention. We have to make sure that, in strong concert with our allies, that we are continuing to press North Korea to change its approach," he said.
The president is paying a visit to South Korea as the nation continues to reel from last week's ferry disaster that left 300 people dead or missing, mostly high school students.
"When our friends are in trouble, America helps, and we'll continue to do everything we can to stand with our Korean friends at this difficult time," Obama said in an interview published Friday by the South Korean newspaper JoongAng Ilbo.
Park has been consumed by the April 16 maritime disaster, which could color the economic and security agenda she had been expected to highlight for Obama.
Meanwhile, North Korea has threatened to conduct another nuclear test, and if that happens while Obama is still in the region tensions could be further heightened.
"President Obama's visit to South Korea sends a strong message to North Korea that its provocative acts cannot be tolerated," Park said.
Contributing: Associated Press