Tense inter-Korean relations following the North's two military attacks on South Korea in 2010 have worsened with Pyongyang's recent threat to carry out a nuclear test. Park has pledged to seek more engagement with North Korea than her predecessor.
"If North Korea uses the coming year to attack South Korea again or conduct another test of a nuclear device or long-range rocket, the possibility of significant near-term improvement in the situation on the Korean Peninsula will evaporate," said David Straub, associated director for Korean Studies Program at Stanford University.
Straub, who served as head of the U.S. State Department's Korea desk from 2002 to 2004, made the remarks during a security forum in Seoul hosted by Yonhap News Agency and the Asia-Pacific Research Center (APARC) of Stanford University.
"The fundamental choices must be made by North Korea, because it is Pyongyang that is on a fundamentally wrongheaded and unsustainable course," Straub said.
Straub hopes North Korea's young leader Kim Jong-un will "understand that the possession of nuclear weapons and the threat and use of conventional force against others are only worsening their own strategic situation."
North Korea has vowed to conduct its third nuclear test in response to the U.N. Security Council resolution tightening sanctions against it as punishment for its December rocket launch. The country previously detonated nuclear devices in 2006 and 2009.
Officials in Seoul have said North Korea appears to have completed all preparations for a test and could detonate a nuclear device at any time.
Some experts said North Korea will not give up its nuclear weapons program and, if this is the case, Seoul and Washington should lay out a new policy of transforming North Korea.
North Korea "celebrated its recent missile test and failed satellite launch as a triumph of North Korean science and technology. Signals of preparation for a third nuclear test, perhaps using highly enriched uranium, are mounting," said Daniel Sneider, associate director for researcher at APARC.
"Neither Seoul nor Washington can or should abandon the goal of rolling back North Korea's nuclear weapons capability. But we need to place that goal within the broader framework of promoting the transformation of North Korea," Sneider said.
"Whether that transformation leads to a Soviet-style collapse or to a successful adoption of the Chinese model, in either case, it would yield a North Korea that is open to the outside world, accelerate the process of economic and social change, likely to lead to political change, and eventually to some form of reunification of the Korean Peninsula," Sneider said.
The Tuesday forum, titled "Yonhap-Stanford APARC International Symposium," brings together a number of former and current government officials from friendly nations under the theme of "Northeast Asia under New Leadership." The conference takes place three weeks before President-elect Park Geun-hye is sworn into office amid near-simultaneous leadership changes in China and Japan.
In addition to North Korea's nuclear standoff, the conference aims to discuss bilateral issues between South Korea and the U.S., as this year marks the 60th anniversary of the signing of a mutual defense treaty between the two countries. The conference will also touch on Sino-U.S. relations under the leadership of Beijing's president-in-waiting Xi Jinping, organizers said.