JERUSALEM, Sept 16, 2025 (AFP) - Israel heavily bombarded Gaza City on Tuesday, witnesses told AFP, after US Secretary of State Marco Rubio backed Israeli Prime Minister Benjamin Netanyahu's new offensive there and its stated goal of eradicating Hamas.

Rubio showed no daylight between himself and Netanyahu on a visit to Jerusalem on Monday, saying Israel could "count on our unwavering support" for its military push in the devastated Palestinian territory.

Hours later, witnesses told AFP there is "heavy, relentless bombing on Gaza City" which levelled homes and left people trapped under the rubble.

"We can hear their screams," said 25-year-old resident Ahmed Ghazal.

Rubio's trip to Jerusalem came despite US President Donald Trump chiding Israel a week earlier for carrying out air strikes on Hamas leaders in US partner Qatar.

But Rubio took a dim view of the Qatari-brokered negotiations for a ceasefire and called Hamas, whose unprecedented October 7, 2023 attack on Israel triggered the Gaza war, "barbaric animals".

The Secretary of State travels to Qatar on Tuesday in an attempt to reassure the emirate, which is home to the largest US air base in the region and has assiduously courted Trump.

Trump told reporters in Washington that Netanyahu "won't be hitting in Qatar" again.

- France presses Palestinian statehood -

Israel has launched a major new military campaign aimed at seizing Gaza City, the territory's largest urban centre, where the United Nations determined last month a million people were facing famine -- a finding rejected by Israel.

Mahmud Bassal, a spokesman for the Gaza civil defence agency, told AFP Tuesday that "bombing is still ongoing heavily across Gaza City, and the number of deaths and injuries continues to rise".

Bassal said the Israeli military also targeted the southern city of Khan Yunis, after the civil defence agency reported Israeli strikes killing 49 people on Monday.

Media restrictions in Gaza and difficulties in accessing many areas mean AFP is unable to independently verify the details provided by the civil defence agency or the Israeli military.

Rubio's visit comes a week before France will lead a UN summit in which a number of US allies, angered by what they see as Israeli intransigence, plan to recognise a Palestinian state.

Rubio called statehood recognition "largely symbolic", while Netanyahu -- whose government is fervently opposed to such a move -- said his country may take unspecified "unilateral steps" in response.

Far-right members of Netanyahu's cabinet have called for annexation of the occupied West Bank to preclude a state, triggering protests by the United Arab Emirates, which took the landmark step of recognising Israel five years ago.

Netanyahu said Rubio's visit was a "clear message" the United States stood with Israel, and called Trump "the greatest friend that Israel has ever had".

Washington's top diplomat, standing alongside the Israeli premier, said "the people of Gaza deserve a better future".

"But that better future cannot begin until Hamas is eliminated," Rubio said at a joint press conference.

The October 7 attack by Hamas resulted in the deaths of 1,219 people, most of them civilians, according to an AFP tally of official figures.

Israel's retaliatory campaign in Gaza has killed more than 64,900 people, also mostly civilians, according to figures from the health ministry that the United Nations considers reliable.

Rubio met privately with hostages' families, who have campaigned hard for their release.

Of the 251 people taken hostage by Palestinian militants in October 2023, 47 remain in Gaza, including 25 the Israeli military says are dead.