Updated

The Bush administration is watching warily, but supportively, as Israel (search) withdraws from the Gaza Strip (search) in an effort to reinvigorate the Middle East peace process.

The State Department condemned an Israeli settler's attack on Palestinians on the West Bank and urged calm on all sides. And Secretary of State Condoleezza Rice called Israeli Prime Minister Ariel Sharon "extremely courageous" for honoring the commitment to the pullout.

At President Bush's Texas ranch Thurday, White House spokeswoman Dana Perino said that he was "getting frequent and regular updates from his staff on the developments."

"The president continues to support Prime Minister Sharon and what he has called a very bold initiative," she said. "It's very courageous. We understand the deep sentiments that are felt and the difficulty one feels when leaving ... their home."

State Department spokesman Sean McCormack told reporters Wednesday "it is a very difficult time for the Israeli people." At the same time he deplored the shooting that left four Palestinians dead and two wounded.

"We condemn this attack, condemn acts of violence committed as part of this withdrawal process, and our condolences go out to the victims' families," the spokesman said. McCormack said the United States had been in touch with the parties in the region to urge calm and respect for the rule of law.

Beyond that incident, the U.S. spokesman said that everyone understood "that this is a very difficult moment for these people who are leaving their homes — in some cases, the only homes they have known."

But McCormack also said the Israeli people understood that the pullout was a step that needed to be taken to realize a more peaceful, stable and secure Israel.

Rice, in an interview with The New York Times published Thursday, said, "Everyone empathizes with what the Israelis are facing" and said that in the interest of advancing peace, "It cannot be Gaza only."

Meanwhile, Daniel Ayalon (search), Israel's ambassador to the United States, charged in an interview with The Associated Press that the Palestinian group Hamas (search) is engaged in a massive buildup of manpower and weapons and must be dismantled.

"They have taken a tactical decision to keep terror on a low flame but not stop it entirely," Ayalon said of Hamas, which remains a potent force in Gaza as Israel withdraws from the territory and part of the West Bank.

Rice said she did not know "how extensive" such a buildup had been. But she also said, "I don't doubt that Hamas is training and increasing its capacity to cause trouble as a terrorist organization."

McCormack said the Palestinians "have shown a seriousness of purpose in working very closely with the Israeli government, in seeing that the withdrawal is a success."

If the withdrawal succeeds, the Palestinian people will be free to move around in Gaza, to go to work, to send their children to school, to go to the beach and so on. "And that's certainly a hopeful thing for the Palestinian people," he said.