North and South Korean officials have opened talks in Pyongyang regarding food aid and other joint-projects.

News reports from Pyongyang say the North Korean delegation delayed Thursday's talks for hours after demanding to see a text of the South's keynote speech, which Seoul refused.

South Korean delegates are to discuss Pyongyang's request for a resumption of rice shipments. The two sides are also expected to talk about a possible test-run of a railway that crosses their heavily fortified border.

South Korea suspended aid shipment in July, after North Korea tested ballistic missiles. Relations worsened when North Korea tested a nuclear weapon in October.

Seoul offered to resume talks with Pyongyang in February, after North Korea agreed to begin closing its nuclear facilities. But North Korea missed an April 14 deadline to begin that process, saying it is waiting for a financial conflict with the United States to be resolved.

South Korea's Yonhap news agency says Seoul's delegation chief, Chin Dong-soo, planned to appeal to Pyongyang to quickly implement the February agreement to strengthen international support for inter-Korean cooperation.

On Wednesday, North Korea's chief cabinet councilor, Kwon Ho Ung, said food aid and the nuclear deal should be separate issues.

North and South Korea remain technically at war because their military conflict ended in 1953 with a truce rather than a peace treaty.

Some information for this report was provided by AFP and AP.