SEOUL, JULY 20 (FRIDAY) -- South Korea will permit North Koreans and South Koreans to cross through their sealed border for five days starting Aug. 13, President Roh Tae Woo announced today.

Roh, in a nationally televised speech described here as historic, called on Communist North Korea to take the same steps by opening its side of the Panmunjom border village. It is unclear whether North Korea, which earlier this month made a vague and narrow proposal for exchanges at the border, will agree to Roh's far-reaching call for unlimited border crossings and unresricted travel.

Roh's proposal reverses a decades-old South Korean policy of sealing its side of the border and jailing anyone who visited or contacted Communist North Korea without official approval -- which was rarely granted. Five months ago, a South Korean court convicted a universitiy student of illegally visiting the North and sentenced her to 10 years in jail. A Catholic priest also on the clandestine trip received an eight-year sentence.

Roh said in his seven-minute speech that the turnabout was sparked by the changing international climate and called for Korean reunification in the 1990s.

"Korea must not remain the world's only land still partitioned by Cold War politics," Roh said. "It is high time that the South and the North embarked on genuine efforts to integrate the Korean people by transcending ideology and politics."

Aside from banning unauthorized travel since the end of the Korean War, the two governments have prohibited any exchanges of mail or phone calls and jammed radio and television broadcasts.

Roh's proposal would permit millions of people on each side of the 38th Parallel to visit their hometowns and meet long-lost relatives, including husbands or wives separated in the war's tumult.

"We will allow {North Koreans} to visit freely any place in the South and meet anyone whom they want to meet," Roh said. "I also hope that like us, the North will accept without restrictions brethren in the South who wish to visit North Korea."

In his speech, Roh said the South Korean government would even pay for the food and lodging of North Koreans who came to the South. He said that if the five-day program worked out, the two governments could hold routine exchanges on holidays before moving to a phase of uninterrupted passage across the border.

This would mark a dramatic change in the hostile relations between the two Koreas and diminish the threat of military confrontation between them. The two Koreas have more than 1.5 million soldiers on either side of the Demilitarized Zone and 43,000 U.S. troops are deployed in the South. Secretary of Defense Richard B. Cheney has called the Korean peninsula one of the most likely sites for a war involving Americans.

Seoul's hostile relations with Pyongyang have marginally improved in the last month, with both sides agreeing in principle to hold a first-ever meeting of their prime ministers in a month or two. It would be their highest-level contact since the peninsula was divided into Soviet- and American-controlled halves after Japan ceded control in the wake of World War II.

A key factor that brought about today's proposal is a new sense of confidence in Seoul. Thanks to its booming economy, a stronger military and the ideological decline of communism, South Korea seems to fear North Korea less than in the past. South Korea long has expressed fear that political destabilization would result from unchecked exchanges -- but it now appears to feel secure enough to cope with them, or that the North would suffer proportionally more tumult.

It is difficult to predict whether the exchange -- focused on the 45th anniversary on Aug. 15 of Korea's liberation from Japanese colonial rule -- will take place. North Korea, despite its previous proposals for exchanges and unification, remains isolated and dictatorial. It has sternly resisted the tide of liberalization changing the Communist world.

Most political analysts in Seoul and Washington suggest North Korean leader Kim Il Sung's rule would be undermined by South Koreans bringing news of changes in the outside world. In a sign of North Korea's fear of information from the outside, its students in Eastern Europe were called home once the revolutions began that toppled Communists there.

But Roh's offer may be difficult to turn down, because by doing so North Korea would be showing a hesitancy to engage in contacts that it officially espouses. The North is under stiff pressure from the Soviet Union and could find itself even more isolated from Moscow, once its main ally but now moving toward establishing diplomatic ties with South Korea.

On the other hand, South Korea may be making the proposal with the expectation that the North would turn it down. It could be logistically impossible to facilitate unlimited border crossings because the only road from Panmunjom to Seoul passes over a one-lane bridge at Imjingak.