JERUSALEM, Israel – Israel may leave buildings in Jewish settlements intact after a Gaza Strip withdrawal instead of demolishing them as initially planned, senior officials said yesterday.

Demolition would force Israeli troops to spend more time in Gaza, exposing them to possible attack by Palestinian Arab terrorists for a longer period and driving up the price of withdrawal, said the head of Israel’s National Security Council, Giora Eiland.

Palestinian Arab leaders have not given a clear preference but have said some of the settlement homes, most of them one-story cottages, would have to be demolished to make room for highrises that could ease a severe housing shortage in densely populated Gaza.

Chief negotiator Saeb Erekat said yesterday he expected Israel and the Palestinian Arabs to discuss the issue, one of many to be resolved ahead of the withdrawal set to begin this summer.

“I don’t think we can afford to have houses that stand on 500 square meters,” Mr. Erekat said.

If the 21 Gaza settlements are left standing, the Palestinian Arabs also would have to ensure that terrorists do not take over the areas.

Palestinian Arab leader Mahmoud Abbas, meanwhile, said Israel and the Palestinian Arabs have an opportunity to make peace and “it would be irresponsible if we, the Israelis, or the world allow it to slip away.”

The Abbas comment was published in the British newspaper The Independent, which said it submitted questions to him last month and the answers were delivered Friday and Saturday.

It was not clear whether Mr. Abbas sent the comment before a Tel Aviv suicide bombing that killed five Israelis outside a nightclub late Friday. The toll rose to five yesterday when a woman died of her injuries.

The Palestinian Arab terrorist group Islamic Jihad claimed responsibility in a statement from the Syrian capital of Damascus, and Israel said it held the Syrian government ultimately responsible.

Israel was briefing foreign diplomats yesterday on what it said was Syria’s role in the bombing. Legislator Yuval Steinitz, head of Parliament’s influential Defense and Foreign Affairs Committee, said “the Syrian government harbors these people [Islamic Jihad leaders], with the intention that they will jeopardize or destroy calm, tranquility and the peace process.”

Asked whether the Syrian government had encouraged the attack, he said: “Yes. Otherwise they would close the offices [of Islamic Jihad] and throw them out of Syria or Lebanon.”

In deciding on the Gaza withdrawal last year, Israel’s Cabinet initially said it would destroy the buildings to save the settlers the grief of seeing Palestinian Arabs – and possibly terrorists – living in the homes. Prime Minister Sharon initially envisioned the withdrawal from Gaza and four West Bank settlements as a unilateral move.

However, with a more moderate Palestinian Arab leadership taking over after Yasser Arafat’s death in November, Mr. Sharon has said he is willing to coordinate the withdrawal with the Palestinian Arabs.

Mr. Eiland said demolishing the homes would increase the cost of the withdrawal by about $18.4 million.

“We advise against destroying the homes,” Mr. Eiland told Israel Radio. “When you weigh the pros and cons … it would be better to try to reach an agreement to hand over the houses in an organized manner … to international or more responsible Palestinian parties.”

Also yesterday, Secretary of State Rice said the new Palestinian Arab government faces a challenge to its authority from terrorists, but the deadly bombing in Tel Aviv need not dim the best hope in years for a Middle East peace deal.

“There are going to be ups and downs in this process; it’s not going to be a straight line,” Ms. Rice said en route to a meeting in London with Mr. Abbas and representatives of European and Arab countries.

All sides have held their breath since Friday’s suicide bombing outside a karaoke club in Tel Aviv, waiting to see if Israel pulled away from the peace process or if Mr. Abbas was powerless to stop further attacks.

Ms. Rice praised what she called “considerable maturity” in the Israeli and Palestinian Arab responses.

“I don’t think we are in the same old pattern,” she said.

She also made clear America expected Mr. Abbas to get tougher.

“Obviously, when you have Palestinian Islamic Jihad taking responsibility, then something needs to be done about that because they are clearly challenging directly the Palestinian Authority,” Ms. Rice told reporters.