Citing reports that Islamic militants were planning additional terror attacks against Israel, Prime Minister Shimon Peres said the closure on the West Bank and Gaza Strip would remain in place.
Peres also told the weekly Cabinet meeting that soldiers at crossings between Israel and the territories had been instructed to check ambulances bringing Palestinians in need of medical treatment into Israel.
The directive was issued after explosives were reportedly discovered on a pregnant Palestinian woman who was being brought to an Israeli hospital.
Israel imposed the closure Feb. 25 after the first of four Hamas suicide bombings during a nine-day period killed scores of Israelis.
In a separate development, Israel on Sunday allowed a group of 200 Palestinian police to enter Gaza via the Rafah crossing from Egypt.
The group, which had arrived from Libya, had been waiting at the border for a month, after two wanted Palestinians were discovered trying to sneak in with the group.
Meanwhile, Palestinian security officials released on Sunday the head of a new Islamic party formed as an offshoot of Hamas.
The Palestinian, Fouad Nahhal, of the Islamic National Salvation Party, was arrested Saturday when he returned home from a meeting with Palestinian leader Yasser Arafat.
Palestinian security officials said he was questioned about his involvement in the series of suicide bombings because he was mentioned by some Hamas activists during interrogations.
Security officials said they released Nahhal after they concluded he was not linked to the attacks.
Hamas activists formed the Islamic National Salvation Party last week to oppose the Israeli-Palestinian peace accords.
The group, which did not adopt armed struggle as part of its platform, reportedly hopes to become the main opposition group to Arafat’s mainstream Al Fatah faction.