Defense Minister Ehud Barak says Israel must have a missile defense system in place to protect it from Palestinian rocket fire before it could carry out a large-scale pullback in the West Bank, an official said Wednesday.

Military experts said it would take between two and a half and seven years to develop a system that would protect Israel from the type of crude rockets that Palestinian militants use.

Militants have launched tens of thousands of Qassam rockets into southern Israel from Gaza in the past seven years of fighting, killing 12 Israelis, the army says. Israelis fear West Bank militants could someday produce the projectiles and launch them into nearby Israeli cities.

A large-scale Israeli withdrawal from the West Bank would be a central component of any final peace deal between Israel and the Palestinians.

Israeli Vice Premier Haim Ramon, a key ally of Prime Minister Ehud Olmert, said last month that he foresaw Israel pulling out of most of the West Bank, except for a few large clusters of settlements, as part of a negotiated peace settlement with the Palestinians.

He did not give a timeline, and following a meeting between Olmert and Palestinian President Mahmoud Abbas on Monday, officials on both sides said there has yet to be any detailed discussion of the borders of a future Palestinian state.

Olmert told Abbas he hopes to launch negotiations “soon.”

Washington has been prodding both sides to make progress ahead of a Mideast peace conference in the U.S. in November, but a final agreement on issues such as borders, the status of Jerusalem and the fate of Palestinian refugees is still seen as distant.

While Barak supports peace efforts, he believes Israel must ensure its security before withdrawing from the West Bank and wants a defense system in place before then, an official close to him said on condition of anonymity because he wasn’t authorized to speak to the media.

Since the Islamic militant Hamas group took over Gaza in June, Israeli experts have warned that Hamas could also wrest control from Western-backed Palestinian President Mahmoud Abbas in the West Bank. Hamas is sworn to Israel’s destruction and is behind many of the rocket attacks from Gaza.

'Iron Dome' project to take years

Israel’s high-tech army has been stymied by the primitive Qassam rockets, which rarely cause casualties but wreak panic. Qassam rockets are airborne only about 20 seconds, making interception difficult, said Shlomo Brom, a reserves brigadier general and senior researcher at Israel’s Institute for National Security Studies.

Israel’s only answer so far is an early warning system that alerts residents just seconds before the projectiles hit.

Israel’s state-owned weapons-maker Rafael is developing a system meant to counter Qassams and the longer-range Katyushas that poured into northern Israel last year during the war with Hezbollah guerrillas in Lebanon. But Brom said it could take six or seven years until the system is ready.

“Thus Barak’s demand is very problematic. It could put off an agreement with the Palestinians indefinitely,” he said.

Israeli lawmaker Ephraim Sneh, who oversaw the birth of the project — named “Iron Dome” — in his former capacity as deputy defense minister, said it would take only about 2˝ years to complete.

Israel is also developing the Arrow missile defense system to protect against the type of longer-range missiles that Syria and Iran have.

Violence persists

In the latest violence, meanwhile, Israeli soldiers shot and killed three Palestinian militants near Israel’s border with the Gaza Strip in two separate incidents, officials said.

Early Wednesday, troops identified two militants approaching the border fence near the Karni cargo crossing, the Israeli army said. Soldiers briefly entered Gaza, exchanged fire with the gunmen and killed them, the army said.

In the second incident, soldiers opened fire at two armed men approaching the fence near the Erez passenger crossing north of Karni, hitting one, the army said.

Hamas said all three were its members.