SEOUL, South Korea (AP) – South Korea’s demand that North Korea renew its commitment to dismantle its nuclear weapons program forced economic aid talks between the neighbors into overtime on Saturday.

The impoverished North’s priority at the talks was to receive food shipments from South Korea, but Seoul has sought to use the talks to persuade the North to implement a February promise to shut down its nuclear reactor.

Meetings were still under way at the economic talks in Pyongyang late Saturday more than eight hours after their scheduled end.

South Korea’s chief delegate, Chin Dong-soo, said the talks would likely continue into Sunday.

“Differences were narrowed on some issues, but other issues need more discussion,” he told reporters.

South Korea appeared to have decided in principle to accept the North’s request for 400,000 tons of rice. In return, it sought to get the North to agree to a mention in their joint statement that its government is committed to the deal to close its reactor in exchange for political and economic concessions, according to pool reports based on South Korean briefings.

However, North Korea contends that the economic talks between the Koreas have nothing to do with the nuclear issue. On Wednesday, the North’s chief delegate walked out of a meeting after his South Korean counterpart raised the nuclear deal.

Also at issue was South Korea’s demand that the North’s military promise to support trial runs of trains on rebuilt tracks across their heavily armed border.

The two sides, however, were close to deal on exchanging raw material for clothes, shoes and soap from the South for the right to develop mineral resources in the North, the pool reports said.

Since February, South Korea restarted most aid shipments to the North that were suspended after North Korea conducted missile and nuclear tests last year.

But the government in Seoul continued to withhold food assistance partly in an attempt to pressure the North to shut down its nuclear reactor, and also in consideration of possible criticism over lavishing aid on the North before it takes steps to disarm.

North Korea failed to meet an April 14 deadline to shut the Yongbyon nuclear facility amid a prolonged financial dispute with the United States.

North Korea boycotted international nuclear talks for more than a year because Washington blacklisted a Macau bank where the communist country held $25 million. America accused Banco Delta Asia of helping the North to launder money and pass counterfeit $100 bills.

America and Banco Delta Asia said earlier this month that the North’s money had been unfrozen. But for unknown reasons, North Korea has yet to withdraw the money.

The two Koreas are still technically at war as the 1950-53 Korean War ended in a truce, not a peace treaty. But their relations warmed significantly since the first and only summit of their leaders in 2000.