Israel "carried out several air strikes... which resulted in the deaths of 13 people and wounded dozens, including women and children, in Khan Yunes and Gaza City", Mahmud Bassal, spokesman for the agency, told AFP.

Israel on Tuesday launched its most intense strikes on the Gaza Strip since a January 19 ceasefire between it and Palestinian militants Hamas ended more than 15 months of war.

The bombardments, which came after the collapse of talks on extending the truce, killed more than 400 people, the health ministry in the Hamas-run territory said.

Israeli Prime Minister Benjamin Netanyahu warned late Tuesday that the strikes were "only the beginning" and that future negotiations with Hamas "will take place only under fire".

"Hamas has already felt the strength of our arm in the past 24 hours. And I want to promise you -- and them -- this is only the beginning," he said in a video statement.

Netanyahu's office also said early Wednesday that the Israeli government had "unanimously approved" his proposal to reappoint far-right politician Itamar Ben Gvir as national security minister.

Ben Gvir had resigned in protest over the January 19 ceasefire agreement, which his Jewish Power party called a "capitulation to Hamas".

Israel has vowed to keep fighting until the return of all the hostages seized by the Palestinian militants during the October 2023 attack on Israel that sparked the war.

Hamas has not responded militarily so far, but in a statement it urged friendly countries to "pressure" the United States to bring to an end the strikes by its ally Israel.