A five-member South Korean delegation was scheduled to fly to Pyongyang on Sunday for three days of talks.
The meetings come just days after a senior U.S. official said North Korea claimed in talks this week in Beijing to have atomic weapons that it might test, sell or use, depending on U.S. actions.
South Korea "will strongly urge North Korea for the abolishment of its nuclear development and change of attitude at the Cabinet-level talks," the South National Security Council said in a statement.
Officials earlier said they feared that North Korea may cancel the meetings. The two Koreas had scheduled Cabinet-level talks earlier this month, but did not meet after North Korea failed to confirm its participation.
Officials said an agenda for the talks would be decided on Sunday in the first round of meetings between the two sides.
The Washington Post reports in its Saturday ediitons that North Korea's declaration that it possesses a nuclear arsenal and might sell some of it to the highest bidder has put new pressure on China to rein in its longtime ally.
For U.S. officials, the grim news from three-way talks in Beijing was tempered by the realization that their long struggle to draw the Chinese into a campaign against North Korea might suddenly bear fruit, the Post points out.
For months, China has been viewed in Washington as a roadblock, unwilling to engage North Korea and actively thwarting action at the U.N. Security Council, the Post says. Now, officials tell the newspaper, they hope to go back to the United Nations with Chinese support for demanding an end to North Korea's nuclear activities.
The talks in Beijing this week, which the Chinese had actively sought, "turned into a debacle for them," the Post quotes a senior administration official as saying. "The problem of nuclear weapons in the Korean Peninsula is more concrete than they thought before."
The North's KCNA news agency on Saturday made no specific reference to Sunday's Cabinet meeting or recent developments in the nuclear dispute.
But in relatively common anti-American rhetoric, it said "the Korean people are standing up to the U.S. imperialists (who are) pursuing a hostile policy toward the DPRK and preparing another war of aggression under the pretext of the 'nuclear issue'." DPRK stands for Democratic People's Republic of Korea, the North's official name.
KCNA also reported that a North Korean foreign ministry delegation left for Britain on Saturday, but did not say why.
The news agency accused the United States of committing more than 2,000 "serious provocations" against North Korea over the past decade.
"But the heroic Korean People's Army has decisively frustrated every provocation, reliably protecting the security of the country," KCNA said.
It listed a string of alleged incidents that included President Bush labeling the North as part of an "axis of evil" along with Iran and Iraq.
The list did not include any incidents since the current nuclear crisis erupted six months ago.
In Tokyo, a senior U.S. envoy told Japanese officials on Saturday that Washington was examining a new proposal offered by North Korea to settle the six-month dispute.
Assistant Secretary of State James Kelly met with Chief Cabinet Secretary Yasuo Fukuda, but refused to discuss the details of Pyongyang's proposal until after consultations with officials in Washington, a Japanese Foreign Ministry official said on condition of anonymity.
In Washington, the White House said it would confer with allies about possibly seeking U.N. sanctions against the North. In the past, North Korea has said it would consider international sanctions a "declaration of war."
The U.N. Security Council expressed concern two weeks ago over the North Korean nuclear dispute, but did not discuss sanctions.
U.S. presidential spokesman Ari Fleischer said Friday the American administration has taken no position on sanctions, but would seek other countries' opinions.
The talks in Beijing were the first high-level U.S.-North Korean contact since tensions over the North's suspected nuclear weapons programs spiked in October.
U.S. officials have said they want the "verifiable and irreversible" elimination of the North's nuclear weapons programs. North Korea has pushed Washington for a nonaggression treaty.
U.S. State Department spokesman Richard Boucher said the United States will not make concessions to North Korea.
U.S. officials said North Korea also told Kelly it had reprocessed spent nuclear fuel rods - a key step in producing nuclear weapons. That claim is not backed up by U.S. intelligence, officials say.