North Korea requested the low-profile meeting between the two sides' top negotiators only hours after South Korea declared Friday that it was pulling out of the Beijing talks due to North Korean intransigence.
But the 90-minute session Saturday morning inside a suite at the swanky China World Hotel played out as inconclusively as the three prior rounds in the drawn-out negotiations.
South Korean Vice Unification Minister Yang Young-Shik and North Korea's Pak Yong Su reiterated the positions they already expressed, South Korean Embassy spokesman Wi Keyei-chul said.
Both sides said they were leaving Beijing, ending the highest level talks between the communist North and capitalist South in 14 months. In both cases, talks broke down over ways to reunite 10 million people separated from relatives 54 years ago in the partition of the Korean peninsula.
After Saturday's meeting failed, Yang accused Pyongyang anew of not negotiating in good faith, thereby violating an agreement last month to discuss family reunions in exchange for Seoul's shipment of 200,000 tons of fertilizer to North Korea.
"We greatly regret that North Korea has not implemented the agreement," Yang said in a statement read by Wi. "We expect the Northern side to respond to the dialogue as agreed."
Pak accused South Korea of not meeting its obligation on fertilizer deliveries.
"They violated the agreement and stuck to only one problem," Pak said.
Half the promised fertilizer was shipped before the talks began. But Yang said Friday that Seoul would send no more until North Korea began discussing the family reunions in earnest.
North Korea, in the fourth year of widespread food shortages, is in desperate need of fertilizer to boost summer crops. Yang said North Korean farmers will need to have the fertilizer in hand by early August for it to do any good.
During the talks, Pak - who once threatened to turn Seoul into a "sea of fire" - and his aides huffily walked out of two sessions and once refused to shake hands with Yang.
Instead of discussing family reunions, Yang said the North Koreans repeatedly raised the sinking of a North Korean gunboat in a naval skirmish last month.
"We greatly deplore that the Northern side used the excuse of the West Sea incident which it provoked," Yang said.