Still, in keeping with their countries' long-standing policies, the two leaders left open the possibility of direct negotiations should the North signal its readiness to end its nuclear pursuits or take other meaningful actions.
"Should North Korea choose the path to becoming a responsible member of the community of nations, we are willing to provide assistance, together with the international community," Park said.
Analysts see some of North Korea's recent bluster as an attempt by the country's new leader, Kim Jong Un, to establish himself as a power player, both within his own country and in the international community. Obama said he knew little about Kim personally and has never spoken to him, but added that his actions were leading him down a dead end.
"There's going to have to be changes in behavior," Obama said. "We have an expression in English, 'Don't worry about what I say, just watch what I do.'"
North Korea ratcheted up its provocations this year after the U.N. Security Council tightened sanctions in response to the February nuclear test, its third since 2006. Pyongyang claims to have scrapped the 1953 Korean War armistice and has threatened nuclear strikes on the U.S., prompting Washington to bolster missile defenses.
While another nuclear test had seemed likely, a pair of launch-ready missiles has been removed from a launch pad, according to two U.S. officials. The officials spoke on condition of anonymity because they were not authorized to publicly discuss a matter involving sensitive U.S. intelligence.
Park's visit was also focused on building a rapport with Obama, who had a close relationship with her predecessor, Lee Myung-bak.
Lee took a hard line on relations with Pyongyang, cutting aid to the impoverished nation. While his approach had Obama's firm backing, public frustration in the South has mounted over the North's continued weapons tests and other provocative actions, including attacks in 2010 that left dozens of South Koreans dead.