SEOUL, JULY 20 -- North Korea today issued a chilly response to South Korea's proposal to open their border for five days next month but stopped short of rejecting it.

Eight hours after President Roh Tae Woo made his proposal, North Korea's news agency carried an official statement demanding that South Korea make several concessions to prove its sincerity. If the demands are met -- an unlikely prospect -- North Korea hinted it will consider opening the border.

Except for an exchange of 151 people from separated families in 1985, neither government has allowed its citizens to visit the other side of the heavily fortified border, the last major front of the Cold War. There is no telephone or mail service between the two sides, and only a trickle of officials and civilians has passed through the Demilitarized Zone since the Korean War, including some northern defectors and southern dissidents.

The awkwardly worded statement by North Korea's Committee for the Peaceful Reunification of the Fatherland demanded repeal of South Korea's National Security Law, release of key political prisoners jailed for breaking that statute by visiting Pyongyang, and the destruction of an alleged wall built along the Demilitarized Zone. Seoul says that only occasional anti-tank barriers straddle the DMZ.

"If the above-said matters are resolved, we will believe what the South Korean authorities said is true and realize a partial travel through Panmunjom," said the statement, monitored by Western news agencies in Tokyo. A separate statement broadcast by Pyongyang Radio was considerably harsher, reportedly calling Roh's proposal "fraudulent propaganda."

The North's cool response was expected. Although it officially has supported the idea of cross-border exchanges, the regime clearly feels uneasy with the prospect of South Koreans traveling around the country and informing the isolated North Korean people about the sweeping political changes taking place outside their Stalinist homeland.

Roh's proposal came in response to a vague North Korean call earlier this month for an exchange at Panmunjom around Aug. 15, the 45th anniversary of Korea's liberation from Japanese colonial rule. That proposal initially was viewed in Seoul as propaganda, but rather than ignoring it the South Korean government decided to call what was seen as North Korea's bluff. Roh's proposal went much further by calling for both sides to open the border at Panmunjom for unrestricted crossings into each other's territory between Aug. 13 and 17.

South Korea's main opposition party warmly welcomed his proposal, and the main dissident group, Chonminyon, said Roh's announcement was a positive step.