Opening the door to a tough new policy, Israel's attorney general determined Friday that relatives of West Bank suicide bombers can be expelled to the Gaza Strip if they encouraged or were linked to terror attacks, officials said.

Palestinian officials and human rights groups denounced the decision and turned to the Israeli Supreme Court to block any expulsions, saying transfer would violate international law forbidding collective punishment and forced deportations.

The militant group Hamas vowed "unique" suicide attacks against Israel if the expulsions were carried out.

Israel sees expulsions as a way to undermine what it sees as one of the incentives for would-be suicide bombers: benefits to their families. Hamas provides schooling and other benefits to its bombers' relatives, and the Iraqi government sends up to $25,000 to the families.

Deportation is sensitive for Palestinians, whose close-knit family relations dictate much of their everyday lives. Deportation to Gaza from West Bank villages where their extended families live would remove much of their social, emotional and economic support systems.

The question of deportation was raised Friday after Israeli forces detained 21 relatives of two Palestinians suspected in back-to-back attacks this week, in which 10 Israelis and two foreign workers were killed — the first deadly attacks on Israeli civilians in nearly a month.

The debate came amid reports of a possible Palestinian cease-fire to set the stage for an Israeli withdrawal on the West Bank. Prince Saud al-Faisal, the foreign minister of Saudi Arabia, said in Washington said the Palestinians were considering such a truce.

Israel has been occupying seven major West Bank towns for the past month to prevent militant operations. But Israelis are questioning whether the incursion is effective after this week's attacks — a West Bank bus ambush Tuesday that killed nine Israelis, and a double suicide bombing in Tel Aviv the next day that killed an Israeli and two foreign workers.

Following the attacks, Israel called off a third round of talks with the Palestinians on improving the humanitarian situation in Palestinian territories. Late Friday, the talks were rescheduled for Saturday night or Sunday, said Nabil Abu Rdeneh, an adviser to Palestinian leader Yasser Arafat. An Israeli official said the meeting would be Sunday.

Attorney General Elyakim Rubinstein determined that Israel could deport relatives of suicide bombers, but only if they were directly involved in acts of terrorism, a Justice Ministry spokesman, Jonathan Beker, said.

Deportations could occur "for example, if they encouraged the bomber to join the terrorist organization or even to volunteer for the suicide attack, or were involved in his recruitment," he said.

Palestinian Cabinet Minister Saeb Erekat denounced the tactic. "When nations in the year 2002 decide on collective punishment, and decide to deport (families) from one place to another, this is a war crime, and we will pursue it as such," he said.

The Israeli human rights group Betselem said the Geneva Conventions specifically ban forced deportations and said such collective punishment "will constitute an unerasable moral blight on the state of Israel."

Attorney Hader Shkirat, director of the Law Society, a Palestinian human rights organization, said he had filed a motion with Israel's Supreme Court as a preventative measure to block any deportations of the 21 Palestinians arrested overnight.

In Washington, State Department spokesman Richard Boucher said the United States expected Israel to act only based on information about a person's culpability, not personal or family relationships.

"We think that taking punitive actions against innocent people will not solve Israel's security problems and we'll be raising that issue with the Israeli government," he said.

An Israeli official, speaking on condition of anonymity, said the government hadn't made a decision on the fate of the 21 men detained overnight.

In the operation, Israeli forces moved into the Askar refugee camp and the nearby village of Tel, near Nablus. Those detained were relatives of suspects accused of involvement in this week's attacks.

In Tel, soldiers destroyed the house of Nasser Aseida, 26, a leader of the Hamas military wing suspected of masterminding the bus ambush. Soldiers detained Aseida's father and four brothers and the relatives of two other wanted Hamas leaders, family members said.

In the Askar refugee camp, soldiers destroyed the house of a leader of the Al Aqsa Martyrs Brigades militia, Ali Ajouri, 23, badly damaging several nearby houses, residents said. Soldiers seized Ajouri's father and two brothers, they said. Ajouri, suspected of dispatching the Tel Aviv bombers, was not captured.

Ranya Ajouri, Ali Ajouri's sister-in-law, said the family had no relation to his activities. "Everyone should be responsible for his own behavior," she said.

The aim of deportations is to counter the support that families of suicide bombers receive from groups such as Hamas and from outside governments, particularly Iraq, which amount to "bribery to commit mass murder," said Daniel Taub, a legal adviser in the Foreign Ministry.

"We've seen mothers appearing in videos of suicide bombers before they go out to commit their atrocities. We've seen families of suicide bombers afterward expressing the wish that their other children will follow suit," Taub said. "We have to try and break this cycle, we have to try and provide a deterrent."

Some experts, however, question if the money really plays a role in bombers' decisions.

The Palestinian Authority also provides a form of social security to families of Palestinians arrested or killed by Israeli forces. Charities funded by other Arab states also contribute.

Israel used the deportation tactic repeatedly in the 1980s, but had largely stopped it until it sent 26 militants to the Gaza Strip in May to end a standoff at Bethlehem's Church of the Nativity.

In December 1992, after a wave of attacks on Israelis, the government expelled about 415 men associated with Hamas and Islamic Jihad to southern Lebanon. After international pressure, Israel allowed them to return. Many of the deportees later used the bomb-making know-how they learned from the militant Hezbollah group in Lebanon to attack Israelis.