Washington - US Secretary of State Condoleezza Rice Friday charged that Hamas is holding the people of Gaza hostage and warned that a ceasefire, to be acceptable, must be "durable."

She said a "durable and sustainable" ceasefire would be one which would not allow Hamas to "continue to launch rockets out of Gaza."

"We're going to continue our work toward a ceasefire that will not allow a return to the status quo ante and that will be durable," Rice told reporterse after briefing US President George W Bush.

On Thursday, as Israel prepared for a major ground offensive into the Gaza Strip, Israel's Foreign Minister Tzipi Livni vowed that her country would continue its offensive until it reaches a point where militants no longer fire rockets at the Jewish state.

More than 400 Palestinians have died in the air offensive that started on the weekend.

Rice said she had no plans to travel to the Middle East. Bush has been in touch with the "major leaders of the Arab states" and with the Israelis, Rice said. She has also contacted European leaders.

"The Hamas has used Gaza as a launching pad for rockets against Israeli cities and has contributed deeply to a very bad daily life for the Palestinian people in Gaza, and to a humanitarian situation that we have all been trying to address," Rice said. "Frankly, Hamas has made it very difficult for the people of Gaza to have a reasonable life." (dpa)