Communist North Korea on Friday offered to open a small stretch of its border to promote unification with South Korea, but its capitalist rival dismissed the gesture as insignificant. The Communist overture came as the prime ministers of the two nations prepared to hold historic talks, perhaps as early as August. North Korea announced it would open the northern sector of Panmunjom, a border village, on Aug. 15, according to Naewoe Press, a semi-official South Korean news agency that specializes in Communist affairs. North Korea said the opening, about 800 yards long and 500 yards wide, was aimed at promoting unification of the Korean peninsula and urged South Korea to do the same, according to Naewoe. ``For successful progress of contact and visits between the north and the south, we will open the portion of our side ... and hope that the south side will take a corresponding measure,'' the agency quoted the Communist government as saying. The opening, however, would not permit foreigners to travel inland, past the perimeter of Panmunjom, a truce village that straddles part of the 155-mile border between the two Koreas. The village is jointly controlled by North Korea and a United Nations Command, comprising the United States and 15 other countries that fought with South Korea in the 1950-53 Korean War. No civilians may enter the area from either side without approval. South Korea's Defense Ministry said it had not been officially notified of the north's plans and would not comment on whether anyone would be allowed to cross the border. But a government spokesman said on condition of anonymity that North Korea's move was ``insignificant'' because it affected only a small, restricted section of the heavily fortified border. Other officials said the move was aimed at dividing opinions in South Korea, where dissidents are pushing for free contacts with their Communist neighbors. The South Korean opposition welcomed the announcement. Dissidents asked Seoul to allow 300 people to meet with North Koreans at the border village Aug. 15, the day in 1945 that Korea was freed from Japanese colonial rule. But a spokesman for South Korea's umbrella dissident group, Chonminyon, said the Seoul response had been negative. The South Korean government bans unauthorized border talks with North Korea. After a five-month suspension, South Korean and North Korean officials have been meeting to discuss an accord that would outline terms for the first talks between their prime ministers. On Tuesday, the Koreas agreed in principle to hold the prime ministers' meeting, possibly in August in Seoul. They agreed to adopt a formal accord July 26. Talks have been held sporadically between the two Koreas, but little progress had been made until recently. The border on both sides is heavily fortified and sealed, blocking exchanges of mail and transportation. North Korea is one of the last totalitarian Communist states, and sweeping changes in Eastern Europe and its socialist allies have made little impact. The two Koreas are still technically at war. No peace treaty has been signed since the three-year Korean War ended in 1953.