"All that we ask the American administration is to take a moral stance towards the Palestinian people, and the Palestinian suffering and to bear its responsibility as a superpower in this world," Ismail Haniya told The Associated Press on Tuesday.
He called on America "to restrain the Israeli aggression and stop it".
"In Gaza, there is what resembles a real human catastrophe," Haniyeh said.
Israel kept up its pressure on Palestinians late on Monday and early on Tuesday, hitting two buildings in Rafah and one in Gaza City from the air.
In the latest violence, Israeli artillery pounded the northern town of Beit Lahiya, killing six Palestinians, all civilians. Three of those killed were children.
"All that we ask the American administration is to take a moral stance toward the Palestinian people, and the Palestinian suffering and to bear its responsibility as a superpower in this world"
Ismail Haniya, the Palestinian prime minister
Late on Monday, Israeli aircraft fired missiles at a four-storey building in the Shajaiya neighbourhood of Gaza City, wounding four, Palestinian security and hospital officials said.
The military said the building was used by Islamic Jihad to store weapons.
Early on Tuesday, Israeli aircraft hit two houses in the southern Gaza town of Rafah after warning the owners to evacuate. Seven people were wounded in the attacks, hospital officials said.
'A day of rage'
Rice arrived in Israel on Monday evening to discuss ways to end the fighting on Israel's second front, where it is battling Lebanon's Hezbollah fighters.
She is meeting Israeli leaders and is to see Mahmoud Abbas, the Palestinian president, on Tuesday, but she will not hold talks with Haniya, whose Hamas party is listed as a terrorist organisation by the US state department.
Palestinians, including Hamas, are planning a general strike and "a day of rage" to protest against the Rice visit, said Omar Assaf, who is helping co-ordinate the strike.
"Rice is responsible for the killing of children in Lebanon and Gaza. She, her administration, and her policies are not welcome here," Assaf said.