The Bush administration has said it would like to see a cease-fire take hold in Gaza, but is strongly defending Israel's air strikes and has not directly called on Israel to hold its fire as other countries have. While many international leaders have called for an "immediate" halt to the violence, State Department Spokesman Gordon Duguid refused to use that term when speaking to reporters Tuesday, calling instead for a "durable and sustainable" cease-fire that produces "lasting peace." He said US Secretary of State Condoleezza Rice had spoken with world figures, including the foreign ministers of Israel, Egypt and Saudi Arabia in pursuit of this goal. "The cease-fire, in order to be productive, has to be maintained," Duguid said. "It can't be a cease-fire in which one side uses it to launch periodic attacks." The White House, in statements Monday, used similar language while placing the blame for the current flare-up squarely on Hamas. "In order for the violence to stop, Hamas must stop firing rockets into Israel and agree to respect a sustainable and durable cease-fire," Gordon Johndroe, White House deputy press secretary, told reporters during a briefing in Crawford, Texas on Monday. "That is the objective to which all parties need to be working, and that is what the United States is working towards." He declined to take a stance on a possible Israeli ground invasion when asked, but said he considered such a measure to be "part and parcel of the overall operation" in the Israeli view. Johndroe added that the US remains concerned about the humanitarian situation in Gaza but that, "The United States understands that Israel needs to take actions to defend itself." US President George W. Bush spoke by phone to Jordanian King Abdullah about the violence Monday and with Saudi Arabian King Abdullah on Saturday. Rice also spoke with President-elect Barack Obama to keep him apprised of the situation and his transition government readies to take the reins on January 20. The timing of the operation seems to help Israel, as the upheaval of the period tends to limit the forcefulness of the US response under a lame duck president should it want to see restraint. At the same time, with Bush's historically strong support for Israel, there's also a sense that Israel wanted to take action under the current administration before a new leadership comes in. Also, with Obama having pledged to change the US image in the world and work more intensively with allies, Israel would like to avoid a situation in which its actions in Gaza pose the first foreign relations challenge for the incoming president. And if it succeeds in weakening Hamas, Israel would be in a stronger position in any new peace talks Obama might seek. Though Obama's team has stressed that there is only one president at a time, top adviser David Axelrod did say Sunday that Obama "wants to be a constructive force in helping to bring about the peace and security that both the Israelis and the Palestinians want and deserve," and though the recent violence complicates the situation, "it's something that he's committed to." "He's going to work closely with the Israelis. They're a great ally of ours, the most important ally in the region," Axelrod said. "But he will do so in a way that will promote the cause of peace, and work closely with the Israelis and the Palestinians on that - toward that objective." Johndroe also stressed the Bush administration's continued commitment to the Annapolis peace process, saying that, "We also want to see, as I've said, the cease-fire restored in a sustainable and durable fashion, so that we can get back on the road map, work towards the goals of the Annapolis process, which, again, is two states living side by side in peace." Yet the parties have acknowledged that the goals of the Annapolis process, namely getting a peace deal in the immediate future, are unlikely to be met. The fading prospects of process have helped free Israel's hands in taking action, since American concerns that such an attack could sabotage the process helped stayed Israel's hand in previous months. Also on Monday, several Congressional leaders weighed in on the Gaza violence, many of them strongly supporting Israel's right to self-defense while expressing sympathy for Palestinian civilians. "Hamas and its supporters must understand that Gaza cannot and will not be allowed to be a sanctuary for attacks on Israel," said US Speaker of the House Nancy Pelosi. "The United States must continue to do all it can to promote peace in the region and a negotiated settlement to differences between Israelis and Palestinians." Howard Berman, chairman of the House Foreign Affairs Committee, stressed, "Israel has a right, indeed a duty, to defend itself in response to the hundreds of rockets and mortars fired from Gaza over the past week. No government in the world would sit by and allow its citizens to be subjected to this kind of indiscriminate bombardment. The loss of innocent life is a terrible tragedy, and the blame for that tragedy lies with Hamas."