Mohammad Dahlan, who is coordinating with Israel over its pullout, warned international institutions and other prospective buyers on Saturday that nearly all land would stay in Palestinian Authority hands after the withdrawal from occupied Gaza this summer.
"These properties inside the settlements are the property of the Palestinian people ... I warn against any sale because it will be wrong and null," Dahlan told reporters, referring to any sales of land or infrastructure by departing Israelis.
"We will not sell, and we will not allow the sale of any of these properties to either local or international parties."
About 5% of the settlement land is privately held and may be returned to Palestinians who can prove ownership, Dahlan said.
Israel plans to withdraw its troops and evacuate all 21 settlements in the Gaza Strip and four of 120 in the West Bank this year under Prime Minister Ariel Sharon's plan to "disengage" from conflict with the Palestinians.
Palestinians fear the plan is an Israeli ruse to give up the Gaza Strip while sealing its hold on the West Bank.
Palestinians want both the Gaza Strip and the West Bank, captured by Israel in the 1967 Middle East war, for a future state.
Dahlan, who met with Israeli Defence Minister Shaul Mofaz on Thursday, said he was seeking information from Israel about a timetable for the Gaza pullout as well as on what infrastructure would be left behind.
Control of borders
"We want to know everything. We want also to know what the status will be with Gaza. Are they going to close it or not? What will happen with the borders?" he asked.
"Withdrawal will not be complete unless we assume control of
borders, passages, the seaport and the airport."
Israel has yet to announce a final decision on whether it will withdraw from a flashpoint corridor along Gaza's southern border with Egypt, where resistance groups have smuggled weapons through tunnels to fight the Jewish state.
The border with Egypt is Gaza's only direct outlet to the outside world, although the impoverished strip has several crossings with Israel.
Palestinians hope after Israel's pullout they can build a seaport and reopen an international airport built in the 1990s.