JERUSALEM — Like Sunday's Hezbollah rocket attack in Northern Israel, Tuesday's suicide bombings in Rosh Ha'ayin and Ariel have led to an Israeli diplomatic offensive, not a military one.

Senior diplomatic officials said no major military reaction to the attacks should be expected, because Israel has no interest in escalating the situation.

Rather, Prime Minister Ariel Sharon used the attacks as further evidence to prove to visiting Assistant Secretary of State William Burns that the Palestinians are doing nearly nothing to fight the terrorist infrastructure.

Sharon briefed Burns, in Israel for a day as part of a regional swing, on what Israel knows about those who carried out the attacks. Sharon informed Burns, accompanied at the meeting by U.S. Ambassador Dan Kurtzer, that the suicide bomber in Rosh Ha'ayin came from a rogue Fatah-Tanzim cell operating out of Bethlehem, which is under Palestinian Authority security control.

Sharon told Burns this development makes it increasingly difficult for Israel to hand over any additional West Bank cities to the Palestinian Authority as the Palestinians are demanding since the Palestinian Authority is unable to take control of the cities they have already been given.

Sharon also raised the security fence issue with Burns, saying that had the fence already been constructed around Rosh Ha'ayin and Ariel, it would have taken the terrorists more time to enter these communities. Had the security services had this extra time to deal with a terrorism alert regarding Rosh Ha'ayin, they may have been able to prevent that attack, Sharon said.

Sharon said the more the security situation deteriorates, the more pressure there will be to build the fence.

One senior official in the Prime Minister Office said that, despite press reports to the contrary, there has been no decision to alter the route of the fence and move it west of Ariel because of massive U.S. pressure.

Shortly after the attacks, Sharon said Israel will not continue with the road map process if the Palestinians do not fight terrorism.

"We see that the Palestinian Authority is not doing what it must do, and the first thing it must do is dismantle the terrorist organizations, disarm them and uncompromisingly fight terrorism," Sharon said during a tour of Beit Dagan. "Unfortunately, the Palestinian Authority is not taking these things seriously."

The Palestinian Authority condemned the attacks, but Palestinian Authority Prime Minister Mahmoud Abbas said they were provoked by recent Israeli anti-terror raids in the West Bank.

Abbas said he did not consider Tuesday's bombings a violation of the cease-fire, according to an Associated Press report that cited a Qatari news agency.

Hamas appears to feel the same way.

Mahmoud a-Zahar, one of the leaders of Hamas in Gaza, said the organization was still observing the cease-fire but that "the operations are a natural reaction to the Israeli violations of the cease-fire."

A-Zahar seemed to be referring, in part, to an Israeli operation in Nablus last Friday in which one Israeli soldier and four Palestinians — including two members of Hamas — were killed.

American officials condemned Tuesday's attacks.

Secretary of State Colin Powell said peace is impossible as long as "people continue to participate in terrorist activities, and we see the response to terrorist activities, which are necessary for self-defense."

Powell made his comments at a State Department gathering of Israeli and Arab children from the Seeds for Peace conflict resolution camp.

Powell also emphasized that the United States would continue to work with its partners in the "Quartet" — the United Nations, Russia and the European Union — to implement the road map.

For Israeli officials, one thing remained clear: The cease-fire had not removed the need to fight against terrorism.

"This is not the first terrorist attack during the hudna, and we believe it will not be the last,'' Israel's police chief, Shlomo Aharonishky, said of the Rosh Ha'ayin attack, using the Arabic term for a cease-fire.

In Islamic tradition, a hudna implies a temporary truce during which forces are rebuilt for future rounds of fighting.