"The number one thing that has to happen is that Hamas has got to stop targeting Israeli citizens with rockets. It must stop," Gordon Johndroe, a spokesman for President George W. Bush's National Security Council, told reporters traveling with the president back to Washington.
Johndroe added: "The Palestinians have a choice to make... It's a choice between terrorism or a choice between a political solution that leads to a Palestinian state living side-by-side in peace and security with Israel."
The days of fighting has killed dozens and led Palestinian President Mahmoud Abbas to call off peace talks, just as Secretary of State Condoleezza Rice headed to the region for a week-long trip aimed at boosting the efforts for an Israeli-Palestinian peace agreement.
With U.S. credibility at stake, Rice faces an uphill battle to revive peace talks suspended over the weekend by Abbas. Washington wants those talks to result in a peace treaty by the end of the year but that hope seems increasingly unrealistic.
U.S. officials said Rice would press Abbas and Prime Minister Ehud Olmert to get back to talks despite the violence in Gaza, which Hamas seized from Abbas' Fatah movement in June, but conceded the timing of her long-arranged trip made it difficult.
"The most important thing is to keep moving the talks along," said a U.S. official who asked not to be identified.
The IDF operation has drawn a chorus of international condemnation, with the EU, Turkey and UN chief Ban Ki-Moon accusing Israel of using excessive force. But Johndroe said it is Hamas that is to blame, by inciting the developments when it fired rockets into Israeli cities.
Johndroe would not say whether the United States thought Israel was using excessive force. "We obviously don't want innocent civilians to lose their life," he said. "But I think that started with these rockets that have been fired from Gaza into Israel recently killing and injuring Israeli citizens in some of their bigger cities."
He said Rice would talk to Palestinian President Mahmoud Abbas about his decision to suspend talks because of the violence.
The official stated that despite the fighting the U.S. would continue to pursue its objective of a peace agreement between Israel and the Palestinians by the end of the year. "We are going to keep after it... Keep on pursing it," he said.