The Israel Defense Forces (IDF) said the first plane carrying US armaments arrived at the Nevatim Airbase in southern Israel late Tuesday evening.

"The cooperation between our militaries is a key part of ensuring regional security and stability in times of war,” the IDF said on X, formerly known as Twitter.

Israel’s defense ministry published a video of the shipment arriving. It said on X that the equipment was “procured & brought to Israel by the Israel Ministry of Defense’s DOPP [Department of Production and Procurement], the US Procurement Mission & the International Transportation Unit.”

US pledges support: US President Joe Biden called Israeli Prime Minister Benjamin Netanyahu on Saturday, in the immediate wake of Hamas’ attack, to emphasize his country's continued support for Israel.

In remarks made at the White House Tuesday, Biden condemned the “pure, unadulterated evil” of the Hamas attackers, and confirmed that at least 14 American citizens were among those killed in Israel.

Biden also said he would call on Congress to approve more funding for Israel to help it defend its territory and people. He promised his administration would not allow Israel to run out of ammunition and interceptors for its Iron Dome air defense system, which is intended to shoot rockets out of the air before they strike Israeli territory.

“When Congress returns, I’m going to ask them to take urgent action to fund the national security requirements of our critical partners. This is not about party or politics, it’s about the security of our world, the security of the United States of America,” Biden said Tuesday.

Concern for hostages: White House National Security Council Coordinator for Strategic Communications John Kirby told CNN Tuesday the White House is having “active conversations,” with Israel to try to bring American citizens in Hamas custody home.

Hamas fighters are holding as many as 150 people hostage in locations across Gaza following their raids on southern Israel Saturday, according to Israel's ambassador to the United States.

In a chilling development, Hamas said it would start executing civilian hostages if Israel targets people in Gaza without warning.

“We're obviously going to be developing options, looking at possibilities how we can get them back, how we can get them back with their families," Kirby told CNN's Wolf Blitzer.