Seoul came out in strong support of the UN Security Council's vote on Saturday to impose sanctions on the communist North after it announced it had tested a nuclear weapon for the first time.
But many here see the test as proof that President Roh Moo-Hyun's "sunshine policy" of engaging the North has failed, and complain that millions in aid money was instead used to develop an atomic weapon now threatening the South.
Newspapers lambasted Roh after his government said that, despite the crisis, it would continue with cross-border industrial and tourism projects which have become a key source of cash for the impoverished North.
"The government and the ruling party are advised to please behave like grown-ups," the Chosun Ilbo, South Korea's largest-circulation daily, said in a pugnacious editorial.
"Despite the emergency of having a nuclear-armed enemy just dozens of kilometres away from Seoul, they keep acting childishly," it said.
South Korea has repeatedly said it will not tolerate a nuclear-armed North, and the government quickly issued a statement underlining its willingness to implement the sanctions.
Yet Seoul is still hoping to negotiate a solution and bring Pyongyang back to stalled six-way talks on its atomic programmes, averting a confrontation over sanctions that the North has warned are a "declaration of war."
Vice Foreign Minister Yu Myung-Hwan was to meet later on Monday with Russian Deputy Foreign Minister Alexander Alexeyev, who on Sunday said he had met with North Korean officials and been assured Pyongyang was willing to negotiate.
Meanwhile, Foreign Minister Ban Ki-Moon will reportedly host US Secretary of State Condoleezza Rice and Japanese Foreign Minister Taro Aso on Thursday, as the international community haggles over how to implement the sanctions.
Japanese officials also said Christopher Hill, the lead US negotiator in the stalled six-way talks, would hold meetings in Japan before going on to South Korea.
But cracks in the global consensus were already emerging as the United States publicly pressed China to enforce the resolution, including inspections of cargo in and out of the North that Beijing had opposed.
"I'm quite certain that China has no interest in seeing the proliferation of dangerous materials from North Korea," Rice said Sunday.
After China, South Korea is the main provider of food and aid to the North, where many South Koreans have relatives that they have not seen since the peninsula was divided six decades ago.
Despite those ties, however, new polls show that nearly 80 percent of South Koreans believe Roh's carrot-and-stick approach, aimed at coaxing Pyongyang's isolated regime back into the international fold, should now be abandoned.
"The government should drastically change its way of thinking," the JoongAng Daily said, urging Roh to abandon the joint projects in the North -- Mount Kumgang, a tourism site, and the Kaesong industrial complex.
"If the government continues these projects, there will be no real profit for them. It would instead bring conflict with the United States and raise criticism of not upholding the (UN) resolution," it said.
The United States, one of South Korea's main allies, is also coming under increasing fire here over the North's test.
A new poll Monday by the Korea Times found that 43 percent of South Koreans blame Washington for the test, with only 37.3 percent blaming the North Koreans who actually carried it out.
The results appeared to be a sign of growing doubt about US commitment to achieving a diplomatic end to the crisis instead, as North Korea says it fears, of wanting to simply topple Pyongyang's communist leadership.
"The isolationist regime's sense of the US security threat may be overblown but not entirely groundless," the paper said. "So far, the Republican administration's North Korea policy has been a total failure."

Copyright AFP (Agence France-Presse), 2006