A top Mideast envoy warned Sunday that the Gaza Strip was in danger of becoming a giant prison if Israel and the Palestinians do not conclude an elusive deal on Gaza's border crossings, an official close to the mediator said.

Palestinians want accommodations that would speed up the flow of goods to revive their shattered economy and allow them freer movement. For Israel, security considerations remain paramount.

International envoy James Wolfensohn is frustrated because after five months of talks, Israel and the Palestinians have not been able to clinch an accord on crossings between Gaza and Israel or the key Gaza crossing into Egypt, an official close to Wolfensohn said on condition of anonymity because he is not authorized to speak to the media.

If the talks do not come to fruition, Gazans will not be able to leave the coastal strip, and that sounds like a giant prison, the official quoted Wolfensohn as saying.

The next 72 hours are crucial because Wolfensohn, the former World Bank president, is leaving the region Wednesday, the official said. Secretary of State Condoleezza Rice is due to begin a two-day visit to Israel and the Palestinian Authority on Sunday.

Meanwhile, violence flared late Saturday as Israeli forces shot and killed a Palestinian militant in the West Bank town of Jenin, the Israeli military said Sunday. It was unclear whether the militant, a local leader of the Al Aqsa Martyrs' Brigades, posed an immediate threat to soldiers when they killed him.

Wolfensohn told reporters he was more hopeful about reaching a deal on the Gaza-Egypt crossing — Gazans' main gateway to the world — before reaching a deal on Karni, the Palestinians' main cargo crossing with Israel.

He said after touring Karni that he believed Rice could speed up a deal.

"I do believe that Secretary Rice is very keen to make sure that the deal is done," said Wolfensohn, who will meet with Israeli and Palestinian officials during the next few days.

Palestinian Cabinet Minister Mohammed Dahlan also used the prison metaphor to describe the Gaza Strip, saying that since Israel's withdrawal in September, "Gaza became an even bigger prison."

"We hope that Ms. Rice's visit will help to contribute to the conclusion of a comprehensive deal," and not just address minor issues, he said.

The international community wants a deal sealed well before the Jan. 25 Palestinian parliamentary election to boost moderate Palestinian leader Mahmoud Abbas, who is fighting off a stiff challenge by the Islamic militant group, Hamas.

Right now, goods at Karni pass through an opening in a concrete wall Israel built to keep out Palestinian attackers. They are unloaded on one side, taken through scanners or security rooms with bomb-detecting dogs, then stacked onto vehicles on the other side in an extremely slow procedure.

Israel has balked at letting through a specific number of trucks and people every day. The Palestinians have said they would try harder to keep militants away but have not presented a plan.

The official close to Wolfensohn said the envoy is "guardedly optimistic" about reaching an accord soon on reopening the Gaza-Egypt border crossing at Rafah, which Israel closed before it pulled out, promising it would be upgraded and reopened within six months.

Abbas promised not to reopen it without Israeli approval, but his government has been pushing to get the key crossing opened earlier. Talks between the two sides have slowed over Israel's demand to monitor the Rafah crossing via closed-circuit TV.

The Palestinians say European monitors to be stationed there should be enough to stop militants and weapons smugglers.

The militant killed in the West Bank was one of three Palestinians that an Israeli patrol shot at because it believed they were going to open fire on a nearby military post, the military said.

After the Palestinians fled, the patrol found an AK-47 assault rifle lying outside a house with bloodstains nearby, the military said. Soldiers sent in a search dog and found the militant, Shoga Balawi, 20, armed with a handgun in a yard. They opened fire and killed him, the military said.