Tel Aviv's traditional ally the U.S. has ordered one of its aircraft carriers to move closer to Israel and offered fresh military aid after a surprise attack by the Palestinian resistance group Hamas.
The Pentagon said it was sending the aircraft carrier USS Gerald R. Ford and its accompanying warships to the eastern Mediterranean while boosting fighter aircraft squadrons in the region.
U.S. Central Command (CENTCOM) confirmed Sunday afternoon that ships and planes had begun moving to their new posts.
The White House moved quickly to affirm U.S. backing for Israel after Saturday's surprise attack from the Gaza Strip, vowing "rock solid" support and warning other parties to stay out of the conflict.
Biden on Sunday spoke to Israeli Prime Minister Benjamin Netanyahu and "conveyed that additional assistance for the Israeli Defense Forces is now on its way to Israel with more to follow over the coming days," the White House said.
"The leaders also discussed ongoing efforts to ensure that no enemies of Israel believe they can or should seek advantage from the current situation," it said in a statement.
Hamas later accused the United States, a major supplier of arms to Israel, of "actual participation in the aggression against our people" by moving the aircraft carrier.
The Israeli-Palestinian conflict's worst escalation in decades has claimed more than 700 lives on the Israeli side, according to the military, while Gaza officials reported at least 400 deaths in Israeli airstrikes.
Netanyahu has steeled his shocked nation for what he called a long war ahead, with tens of thousands of Israeli forces already deployed to battle holdout Hamas forces and prepare a possible Gaza ground offensive.
The conflict has stoked fears of a wider conflagration. Lebanon's Iran-backed Hezbollah movement said Sunday it had fired shells and missiles at Israeli positions.
With tensions rising, U.S. Defense Secretary Lloyd Austin said he was sending forces to "bolster regional deterrence efforts" after discussions with Biden.
As well as the USS Gerald R. Ford carrier, this deployment includes a guided missile cruiser and four guided missile destroyers, Austin said in a statement.
"The United States government will be rapidly providing the Israel Defense Forces with additional equipment and resources, including munitions," added Austin, who also spoke with his Israeli counterpart Sunday.
The movement of U.S. ships and planes and the aid to Israel "underscores the United States' ironclad support for the Israel Defense Forces and the Israeli people."
The United States on Sunday afternoon also led calls for condemnation of the Hamas attack on Israel at the United Nations Security Council.
