The agenda this time should include North Korean assurances that it will take "responsible measures" over the ship sinking and another deadly incident last year and not provoke further tensions, said Lee Jong-joo, a spokeswoman for South Korea's Unification Ministry, which is in charge of inter-Korean affairs.
North Korea launched artillery at a South Korean island in November in an attack that killed four people. It denies, however, attacking the navy ship that sank in March, killing 46 sailors.
Inter-Korean relations have been complicated by a power transition under way in the North, where leader Kim Jong Il is believed to be grooming his youngest son Kim Jong Un to succeed him. Some analysts say the ship sinking and the artillery attack were carried out to display the younger Kim's mettle to North Korea's military and bolster his legitimacy as the next leader.
The Unification Ministry's Lee said North Korea had proposed talks earlier Thursday to ease tensions and "express opinions" about the two incidents. South Korea's Defense Ministry said the North suggested talks at the level of minister.
The ministry said it would suggest preliminary meetings to discuss the timing and other details of the talks.
South Korea will also propose separate talks with North Korea to verify its commitment toward denuclearization, Lee said.
North Korea's state news agency was silent on the proposed defense talks.
South Korea had rejected earlier North Korean calls for unconditional dialogue as insincere. South Korea has also called for an apology from the North.
"North Korea may make gestures in the talks that can be accepted by South Korea," said Jeon Kyong-mann, an analyst at the state-run Korea Institute for Defense Analyses in Seoul.
The two countries' defense chiefs last met in Pyongyang in November 2007, a month after the second summit between the leaders of their countries.
On Wednesday, President Barack Obama and his Chinese counterpart Hu Jintao agreed in talks in Washington on the importance of maintaining peace and stability on the Korean peninsula, and said that communication between the Koreas is a key element for any progress.
"The United States and China emphasized the importance of an improvement in North-South relations and agreed that sincere and constructive inter-Korean dialogue is an essential step," they said.
They also called for measures that would allow an early resumption of six-nation negotiations on North Korea's nuclear programs.
The Obama-Hu talks were closely watched in South Korea due to the important role played by both Washington and Beijing on the Korean peninsula. The U.S. and South Korea have a decades-long security alliance, while China is North Korea's key ally.
North Korea appeared to have made the offer to show the United States and China that it is serious about reducing tensions, said Kim Yong-hyun, a North Korea analyst at Seoul's Dongguk University.
He also said the inter-Korean talks could serve as a "stepping stone for the resumption of the disarmament talks."
Seoul, Washington and Japan have pressed the North to prove it is serious about giving up its atomic ambitions before they will allow a new round of aid-for-disarmament talks.
North Korea has expressed a desire to restart the nuclear talks it quit in early 2009. The talks involve the two Koreas, Japan, the United States, China and Russia.
North Korea conducted two nuclear tests in recent years and is believed to have produced enough weaponized plutonium for at least half a dozen bombs.
The North also unveiled in November a uranium enrichment facility that could give it a second way to make atomic bombs.