President Park Geun-hye on Monday called for national unity and tighter vigilance against North Korea, noting the communist state is seeking to trigger division in South Korea and a "crack" in international cooperation against its nuclear development.

During a Cabinet meeting, Park also warned against "isolationism and protectionism," stressing that South Korea should be at the vanguard of the efforts to overcome them in the wake of Britain's shocking vote to exit the European Union (EU).

"(North Korea) is seeking (to cause) a conflict within our society and internationally, it is making various attempts to cause a crack in the system of international cooperation against North Korea," she said.

"At this juncture, we should ensure that we do not slacken our vigilance and that we put up a united front rather than be divided."

Touching on the recent set of measures by the reclusive state to further reinforce its leader Kim Jong-un's grip on power, Park called on the North to realize that its efforts to stabilize its regime will go nowhere if it focuses on developing nuclear arms and missiles.

"Its attempts to stabilize its regime by threatening the world with nukes and missiles rather than through enhancing its people's livelihoods will never succeed," she said. "These would only invite stronger sanctions by the international community and its regime, after all, will never be stabilized."

Last week, the North's Supreme People's Assembly, its rubber-stamp parliament, gave its leader Kim a new title: the chairman of the newly created state apparatus called the State Affairs Commission. The move is seen as further reinforcing Kim's autocratic rule.

Kim was given the new title amid growing concerns that the country has been constantly developing its nuclear weapons technology and delivery capabilities. Last month, it claimed to have successfully carried out a test on the Musudan intermediate-range ballistic missile, escalating its threats to its potential adversaries including the U.S. and South Korea.

Signaling her concerns about isolationist and protectionist tendencies in the world markets, Park said that the country should turn the current situation into an opportunity to emerge as a pivotal state championing free and open trade.

"In the past, many of the developing states opted for isolationism while pushing for their economic development, but South Korea chose an externally-oriented strategy that promoted economic development and competition, and achieved an economic growth that startled the world," she said.

"Our FTAs have now become our crucial economic assets," she added.

Noting a recent series of terrorist attacks by the Islamic State jihadist group, including those in Turkey and Bangladesh, Park ordered the government to check any vulnerabilities in South Korea and ensure that terrorists cannot enter the country.