Seoul: South Korean President Lee Myung-bak has called for national solidarity against military aggression by the North, saying Pyongyang looks for division in the South as an opportunity to strike.
Lee has sharpened his language against the North after coming under pressure over a perceived weak response to two North Korean attacks this year that raised tension on the peninsula to the highest level since the 1950-53 Korean War.
The clashes have led some analysts to say the chance of a wider conflict is greater than ever.
In the latest rhetorical sparring, the North last week threatened a nuclear "sacred war" and Lee vowed "a merciless counterattack" against any fresh North Korean attacks as rare large-scale military drills by the South kept tension high.
"We can`t afford to have division of `you against me` in the face of national security, because what`s at stake is our very lives and the survival of this nation," Lee said in a national radio address.
Lee said it was divided public opinion after the North`s attack on a South Korean navy ship in March, in which 46 sailors were killed, that had prompted the North to bombard a South Korean island near a disputed sea border last month.
North Korea, a reclusive state that has defied international efforts to curtail its nuclear program, denies responsibility for the ship attack.
"It is when we show solidarity as one that the North dares not challenge us. Their will to challenge breaks," he said.
Lee took office in 2008 and ended a decade of free-flowing economic aid to the impoverished North from his two liberal predecessors that persisted despite previous acts of violence against the South.
But he has come under criticism for being indecisive and ineffective against the North`s military acts.
Analysts said the frequency and severity of aggressive North Korean action had pushed Lee against a political wall and he had little choice but to order harsh retaliation which could spark wider conflict.
A survey by pollster Realmeter showed support for Lee edged higher, above 45 percent, in a poll conducted after he pressed ahead with live-fire military drills this month despite diplomatic pressure from China and Russia to suspend it.
South Korea`s Defense Ministry said there would be more defensive and routine drills at sea off all coasts this week, with some live firing expected, prompting the North to say the peninsula was being pushed to the brink of war.
The United States, which has around 28,000 troops in South Korea, has backed the military exercises and participated in joint drills earlier this year.
The Pentagon said on Monday that Defense Secretary Robert Gates will visit Seoul on January 14, just weeks after the top U.S. military officer traveled there.
Gates and his South Korean counterpart will discuss North Korea`s recent actions and ways the allies can "address the threats posed by North Korean provocations and its nuclear and missile programs," Pentagon Press Secretary Geoff Morrell said.
North Korea`s main newspaper, Rodong Sinmun, on Monday accused South Korea and the United States of trying to start a war and praised the North`s "self-restraint."
"The U.S. and South Korean trigger-happy elements should not misjudge the will of (the North) to preserve peace but immediately stop their reckless military provocations aimed at screwing up the tension on the Korean peninsula," it said.