The Bush administration called Monday for an end to the new flare up in Mideast violence, saying Hamas has "once again shown its true colors as a terrorist organization" with attacks on Israel. White House spokesman Gordon Johndroe said the Hamas organization had chosen not to renew a six-month cease-fire agreement arranged by Egypt. At the same time, he said the United States had asked Israel to avoid civilian casualties in Gaza. The spokesman declined to respond to questions about whether the United States believes Israel is ready to launch a ground attack on Gaza, but said the ultimate goal of Israelis is "for their people to be able to live in peace." Johndroe told reporters covering President George W. Bush in Texas that Bush had spoken early Monday with King Abdullah of Jordan, and had spoken on Saturday with King Abdullah of Saudi Arabia. He also said that Bush had a detailed briefing by video conferencing with Vice President Dick Cheney, White House chief of staff Josh Bolten and national security adviser Stephen Hadley. In Washington, the State Department echoed the White House and said the United States was "vigorously engaged" in trying to restore the cease-fire and make it "durable and sustainable." Spokesman Gordon Duguid said Secretary of State Condoleezza Rice has called her Israeli counterpart, Tzipi Livni, five times since Dec. 26, and said Rice also talked to Prime Minister Ehud Olmert, Defense Minister Ehud Barak and Lebanese Prime Minister Fuad Saniora. She also called Egyptian Foreign Minister Ahmed Aboul Gheit three times and Saudi Foreign Minister Prince Saud al-Faisal, Duguid said. "We are encouraging all the nations in the region to take an active part in rebuilding the cease-fire so that we can return to the relative calm that was enjoyed in the region over the past six months," he told reporters. "We are working for a cease-fire now where Hamas must stop its rocket attacks on Israel. All sides then need to respect the ceasefire." In Crawford, Johndroe said the Israeli actions were "in response to the mortar and rocket attacks on Israel" and said that the United States has asked Israel to avoid civilian casualties in Gaza. Johndroe also said that parties on all sides should clear the way for humanitarian assistance such as food and medical supplies in Gaza. Asked if the administration believes it permissible for Israel to launch attacks in Gaza, Johndroe said: "The United States understands that Israel needs to take actions to defend itself." "Hamas has once again shown its true colors as a terrorist organization that refuses to even acknowledge Israel exists," he said. Johndroe repeated that President-elect Barack Obama is getting daily intelligence briefings "and we will continue to stay in touch with his staff as developments warrant." Johndroe said that "at this time" there are no plans for Bush to speak on the issue. He said he did not want to speculate too heavily on the impact the new violence will have on Palestinian Authority President Mahmoud Abbas. Asked why Hamas broke the cease-fire, "You know, it's hard for me to get into the minds of terrorists ... so it's impossible for me to answer." Asked if the Israelis would be justified in seeking to destroy Hamas if it does not renounce further rocket attacks, he said, "I think what people want is peace on the ground and an end to the violence so people can go about living normal lives, and especially people in southern Israel, who spend so much time living in bomb shelters. It's unacceptable." US Senate Majority Leader Harry Reid said Monday that he strongly supported Israel's right to defend its citizens against rocket attacks from Hamas. "Hamas' failure to stop these attacks only exacerbates the humanitarian situation for the residents of Gaza and undermines efforts to attain peace and security in the region," Reid said in a statement.