Women activists including Gloria Steinem and two Nobel peace laureates said Wednesday they may have to change plans to cross Korea's Demilitarized Zone because authorities can't guarantee their safety if they walk from the North to the South at Panmunjom, the symbolic but tense site where the Korean War armistice agreement was signed.

The rare crossing of the DMZ, which has been approved by both Koreas, is to take place Sunday.

Organizer Christine Ahn, a Korean-American peace activist, said the group of 30 women from 15 countries still intends to march from the northern side of Panmunjom into South Korea. But officials in Pyongyang have informed her that without a formal letter from Seoul approving a crossing at Panmunjom — usually reserved for government missions — they may have to cross at another location.

Ahn said North Korea approved the crossing and has requested confirmation with Seoul through the Red Cross. But she said she was informed after arriving with her group on Tuesday that Seoul had not replied. Pending clear approvals from Seoul and the U.N. military command that supervises the DMZ, she said the group has been advised to consider crossing from nearby Kaesong on a highway that is used mainly for civilian and commercial purposes.

"We have approval from both governments to cross the DMZ, but we don't know precisely where," Ahn told The Associated Press at the hotel in Pyongyang where she and the group are staying. "We have every intention of crossing at Panmunjom. However, it seems we are not able to get official responses."

Steinem, an iconic figure in the international women's rights movement, said she wants Gen. Curtis Scaparrotti, the commanding officer of U.S. Forces, Korea and the U.N. Command, to step in and provide security assurances for Korean officials on both sides of the DMZ so that the crossing can go through Panmunjom.

"We appeal to Gen. Curtis Scaparrotti as head of the United Nations Command with jurisdiction over the Joint Security Area to cooperate with our request to cross at Panmunjom," Steinem said. "This Orwellian experience we are having is yet one more demonstration of how insane, and wasteful and cruel and outdated this boundary is."

North and South Korea have technically been in a state of conflict since the 1950-53 Korean War ended in an armistice, not a peace treaty. Their border along the DMZ is one of the most heavily fortified in the world. There is little direct contact between the two Koreas and, with few exceptions, it is considered a crime for citizens of either country to cross the DMZ.

The difficulty Ahn's group has faced underscores the fear that even a minor misstep at Panmunjom, where North and South Korean soldiers stand guard within shouting distance of each other, could quickly escalate into major incident. Kaesong, on the other hand, is the location of a joint North-South industrial complex and that route would have immigration and customs facilities.

"We want to cross at Panmumjom because it's been 62-plus years that we've allowed our government leaders to try to break the impasse and the stalemate. Sorry, you haven't succeeded," Ahn said. "We want to cross there. It has huge symbolic importance and we haven't come all this way to just cross where trucks carrying cargo cross. Panmunjom is why we have come."

Also on the trip are Nobel Peace Prize laureates Mairead Maguire and Leymah Gbowee. Maguire received the Nobel prize for her work toward ending the conflict in Northern Ireland and Gbowee for her role in the Liberian peace movement.

The group is spending several days in North Korea before the march meeting with North Korean women, touring hospitals and factories and holding an international women's peace symposium.

After the crossing, they also plan to hold a peace march and a symposium in South Korea.