By Nidal al-Mughrabi
GAZA (Reuters) - Israeli warplanes attacked government buildings in the Gaza Strip on New Year's Day after Israel and its Islamist Hamas foe both spurned cease-fire calls in a conflict that has killed about 400 Palestinians.
Israeli tanks and troops were massed near the border of the Hamas-controlled territory and the Haaretz newspaper reported on Thursday the Israeli army had recommended a major but short-term ground offensive into the densely populated enclave.
In fresh raids on the sixth day of hostilities, Israeli aircraft and naval forces attacked about 20 Hamas targets in the Gaza Strip, the Israeli military said.
Hamas security officials said buildings housing the education and transportation ministries had been virtually destroyed. The Palestinian parliament building was also hit, they said. Gazans who ventured out of their homes walked along rubble-strewn streets to survey the destruction.
Hamas rockets hit the southern city of Beersheba on Wednesday, scaring residents and hardening Israel's resolve to stamp out a threat that has killed three Israeli civilians and a soldier since hostilities broke out on December 27.
Foreign pressure grew on both sides to hold their fire but Israel brushed aside as "unrealistic" a French proposal for a 48-hour truce that would allow in more humanitarian aid for Gaza's 1.5 million residents.
In New York, the U.N. Security Council held an emergency session but adjourned without a vote after Arab countries pushed for a demand for an immediate cease-fire. Western delegates described the Arab-drafted resolution as unbalanced and said negotiations would continue to reach an agreed text.
Diplomats said the deadliest conflict in the Gaza Strip in four decades could get even bloodier after days of air strikes that have killed at least 396 Palestinians, about a quarter of whom, U.N. figures showed, were civilians.
France said it would host Israeli Foreign Minister Tzipi Livni on Thursday and an Israeli official said French President Nicolas Sarkozy planned to visit Jerusalem on Monday.
Israel Radio said Israeli forces massed at the Gaza border were readying for a possible ground offensive.
"This is only the beginning," Israeli Deputy Defence Minister Matan Vilnai said on Israel's Army Radio.
"We are operating now, for exactly what we have said from the start, and nothing has changed, to deal Hamas a heavy blow. It has already been wounded." He said Israel would insist on an end to all rocket fire from Gaza.
The Gaza operation, launched after a six-month cease-fire expired on December 19 and Hamas intensified rocket strikes, could affect the outcome of the national election Israel is to hold on February 10.
A poll in the Haaretz daily showed a majority of Israelis, 52 percent, favoured pursuing the attacks in Gaza, with just 20 percent backing calls for a cease-fire, and 19 percent favouring the launch of a ground offensive into Gaza.
Hamas leader Ismail Haniyeh said Israeli attacks must stop before any truce proposals could be considered. Israel must also lift its economic blockade of Gaza and open border crossings.
"After that it will be possible to talk on all issues without any exception," Haniyeh said in a televised speech.
U.S. President George W. Bush spoke by phone to Israeli Prime Minister Ehud Olmert, the White House said. Bush put the onus on Hamas to stop firing rockets as a first step to a truce.
Olmert told his security cabinet that if a diplomatic solution could be found that ensured better security for southern Israel, the government would consider it.
"But at the moment, it's not there," an aide quoted Olmert as saying. "We didn't start this operation just to end it with rocket fire continuing as it did before it began."
Israeli ministers approved the mobilisation of 2,500 army reservists, expanding on an earlier call-up of 6,500 soldiers for the force on the Gaza border.
Rain that could impede an armoured invasion largely cleared on Thursday and forecasters predicted clear skies for the next several days.
Food supplies in Gaza were running low and there were power cuts. Hospitals struggled to cope with the high number of casualties from the offensive.
Israel said it would continue to let humanitarian supplies into Gaza and that more than 90 truckloads with food and medicine would be permitted into the territory on Thursday. A similar amount of supplies went in on Wednesday.
(Additional reporting by Adam Entous, Ari Rabinovitch, Jeffrey Heller and Ori Lewis in Jerusalem, Wafa Amr and Ali Sawafta in Ramallah, Patrick Worsnip at the United Nations, James Mackenzie in Paris and Alaa Shahine in Cairo; Writing by Angus MacSwan and Allyn Fisher-Ilan; Editing by Keith Weir)