GAZA CITY, Gaza Strip ? Three major Palestinian groups declared a temporary cease-fire Sunday after 33 months of violence, and Israel pulled out of part of the Gaza Strip — breakthroughs in the U.S.-backed bid for peace.

The militant Islamic Jihad and Hamas groups announced a joint three-month cease-fire, while Yasser Arafat’s Fatah faction declared a six-month truce.

Israel expressed doubts about the promises and insisted the Palestinian Authority must disarm the militants. The Bush administration welcomed news of the cease-fire but said it wanted to see more progress in the so-called “road map” to peace.

“Anything that reduces violence is a step in the right direction,” White House spokeswoman Ashley Snee said. “Under the road map, parties have an obligation to dismantle terrorist infrastructure. There is still more work to be done.”

Hopes for a turning point in the conflict also were boosted by a new security deal in which Israel was handing the Palestinian Authority control of a key area of Gaza.

Scores of Israeli armored vehicles pulled out of the northern Gaza town of Beit Hanoun after sundown, in line with a weekend agreement to restore Palestinian security control over some areas Israel reoccupied during the more than 1,000 days of fighting.

Sunday’s rapid-fire developments came as U.S. National Security Adviser Condoleezza Rice had talks with Israeli Prime Minister Ariel Sharon in Jerusalem, a day after meeting with his Palestinian counterpart, Mahmoud Abbas.

Seeking to build on the advances, Rice is talking to both sides about further steps in enacting the road map to Mideast peace and Palestinian statehood by 2005, launched by President Bush at a June 4 summit.

For weeks, violence has bedeviled attempts to begin the plan. On Sunday, the death toll stood at 2,414 on the Palestinian side and 806 on the Israeli side.

Abdel Aziz Rantisi, a Hamas leader, read the Islamic militants’ truce announcement in a phone call to The Associated Press. “The two movements decided to suspend military operations against the Zionist enemy for three months, starting today,” Rantisi said.

Islamic Jihad leader Mohammed al-Hindi confirmed the truce took effect Sunday.

Despite the progress, violence continued Sunday. The army said Palestinian gunmen opened fire at settlers in Kiryat Arba, near Hebron in the West Bank. Israeli security forces fired warning shots. There were no reports of injuries.

A Palestinian boy waves a flag while others wave the victory sign after Israeli soldiers withdraw from the Beit Hanoun crossing in northern Gaza. Israeli troops and tanks began pulling out of northern Gaza after sundown Sunday, military sources said, in keeping with an agreement to hand responsibility for security in Gaza over to the Palestinians.