The administration informally notified the weapons package to Congress, which will need to approve it, a US official said, while a congressional aide who also requested anonymity said the weapons bought from US weapons makers amounted to around $1 billion.

The weapons would come out of a major $95 billion package recently approved by Congress in defense support for Ukraine, Israel and Taiwan, and the Biden administration has repeatedly said it planned to go ahead and appropriate the funds through purchases from US manufacturers.

But the deal comes a week after Biden warned he may withhold bombs and artillery shells to Israel if Prime Minister Benjamin Netanyahu went ahead in defiance of US warnings with an assault on Rafah, the southern Gaza city where more than one million Palestinians have taken shelter after half a year of war.

The Biden administration also confirmed last week that for the first time it had halted a shipment including 2,000-pound bombs, fearing they would be used with devastating risks for civilians in Rafah.

Congress could still block the weapons sale to Israel, with left-leaning members of Biden's Democratic Party outraged by the toll on civilians in the Gaza war.

But the overall package passed despite opposition from the left, with the rival Republican Party almost unanimously in support of arms for Israel.

The Wall Street Journal first reported the new arms package. It said it could potentially include $700 million in tank ammunition and $500 million in tactical vehicles.

The Biden administration, while increasingly critical of Israel, has made clear it will continue to support its ally's security and pointed to US assistance last month in shooting down Iranian drones launched in retaliation for a strike on a diplomatic facility.

"We are continuing to send military assistance, and we will ensure that Israel receives the full amount provided in the supplemental," Jake Sullivan, Biden's national security advisor, told reporters on Monday.

"We have paused a shipment of 2,000-pound bombs because we do not believe they should be dropped in densely populated cities. We are talking to the Israeli government about this," he said.

Since the October 7 Hamas attack that triggered the massive Israeli retaliation, the Biden administration has twice cited emergency needs to avoid the regular 30-day review by Congress of military transfers.

Critics also point out that the Biden administration has sent a regular flow of weapons unknown to the public as they fall below the threshold for congressional notification.