American special Mideast envoy George Mitchell should make a stop at Tel Aviv's Platinum Tower on his next visit to Israel for a chat with former prime minister Ehud Olmert. He will find it interesting. Olmert will tell him that on September 13, 2008, after he resigned and became caretaker prime minister, he hosted Palestinian President Mahmoud Abbas in his home in Jerusalem and presented him with a detailed proposal for a peace agreement.

In their previous meeting two weeks earlier, Olmert had presented a map of the Palestinian state, but Abbas complained that it was too small. This time Olmert prepared a giant map of the future border and its twisting route, which he drew with the help of an external expert.

Olmert's map proposed that the Palestinians establish their state on 93.5 percent of the West Bank, receiving another 5.8 percent through a land exchange with Israel. The rest would come in a "safe passage" corridor from the West Bank to the Gaza Strip. The map left the settlement blocs in Israel's control - Ma'aleh Adumim, Ariel and Gush Etzion - proposing in exchange lands in the southern Hebron Hills, the Judean Hills and the Beit She'an Valley. According to the Palestinians, Olmert also proposed dividing the no-man's-land near Latrun. All told, Abbas was offered an area equal to the whole West Bank - 100 percent.

As for Jerusalem, Olmert proposed dividing sovereignty between the Jewish and Arab neighborhoods, and leaving the Old City's "holy basin" and its surroundings without sovereignty, under the management of an international committee with the participation of Israel, Palestine, the United States, Jordan and Saudi Arabia.

The most original suggestion involved the refugee issue. Olmert did not recognize the Palestinians' demand for a right of return. Rather, he agreed to take in a small number of refugees over five years, "about the number of people that can fit into the Muqata [Palestinian government headquarters] in Ramallah" - that is, between 2,000 and 3,000 people.

According to the Israeli version, Abbas asked Olmert to let him have the map. "If you sign it, you can have it," Olmert told Abbas. He did not want to give the Palestinians a document that would be a baseline for the next round of negotiations and a basis for demanding more concessions from Israel. Abbas responded that he wanted to study the details with a cartographic expert and return the next day with chief negotiator Saeb Erekat and the cartographer for another meeting. Olmert agreed.

But Abbas did not return the next day, or the day after. He did not even call. He severed contact and eventually explained in an interview with The Washington Post that he had rejected Olmert's proposal because the gaps were too wide. According to Erekat, the Palestinians demand full sovereignty over the Temple Mount and are not prepared to hand it over to an international body. They also want to shrink the settlement blocs that Olmert wanted to annex to Israel. But that version was given later, not as a direct answer to Olmert. Only after Olmert left office did Abbas call to say goodbye.

What can we learn from this story? The political reactions are predictable. The right will argue that once again the Palestinians rejected a generous offer and this is more proof that there is no one to talk to and nothing to talk about. Netanyahu's office regards the interview in which Abbas admitted to rejecting the offer as a priceless public-relations asset. The left will argue that Olmert did not offer enough.

Political debate aside, the essential lesson from Olmert's proposal is that the parties' stances have hardly changed since the failures of Camp David and Taba. Nine years of war, diplomatic standstill and thousands killed on both sides have not softened them. The Palestinians have not given in and Israel has not broken. Apparently a compromise can be reached on borders, but Israel does not want Palestinians to return to its territory and the Palestinians want the Temple Mount. Neither side is prepared to give up its national symbols and tell its people that the pledges of the past - "we will return to our villages in Palestine" and "united Jerusalem in Israel's hands forever" - were just illusions.

The second lesson is procedural. Left to their own devices the parties cannot reach an agreement. They need close oversight by an external mediator, preferably American, to bridge the gaps and propose incentives in exchange for painful concessions. That needs to be the role of U.S. president Barack Obama and his emissary, Mitchell.