The State Department revealed that U.S. government employees and their family members are now prohibited from undertaking any personal travel in Israel outside of the greater Tel Aviv, Jerusalem and Be’er Sheva areas "until further notice."

The alert says the restrictions were imposed "out of an abundance of caution" and shared to help other Americans in Israel make their own security plans.

"In response to security incidents and without advance notice, the U.S. Embassy may further restrict or prohibit U.S. government employees and their family members from traveling to certain areas of Israel (including the Old City of Jerusalem) and the West Bank," the alert adds.

Asked whether the limitations were directly connected to Iran’s threats, State Department spokesperson Matthew Miller declined to speak to the specific assessments motivating the policy but acknowledged the public warnings from Iran and said Israel is in "a very tough neighborhood."

"Clearly we are monitoring the threat environment in the Middle East and specifically in Israel, and that's what led us to give that warning to our employees and their family members and to make it public so all U.S. citizens who either live in Israel or traveling there are aware of it," he said.

-ABC News' Shannon Crawford

Gen. Michael Erik Kurilla, the commander of U.S. Central Command, is set to meet with officials in Israel about Iran and the Joint logistics over-the-shore floating piers which U.S. military officials currently on the ground in Israel have been working to coordinate with Israeli military officials, an Israeli official told ABC News.

The official said there has been a "marathon of calls" between Israel’s Defense Minister Yoav Gallant and the National Security Council, the State Department and the Pentagon, which the official credits with increasing statements of support by the administration for Israel in case it’s attacked by Iran. Those talks were an extension of the meetings two weeks ago when the White House summoned Israeli officials to Washington to discuss the urgent need to increase humanitarian aid in Gaza.

After months of U.S. calls for Israel to massively increase aid, multiple Israeli security officials tell ABC News that Israel heard the message loud and clear this time.

"We heard what they said about the humanitarian effort," the official told ABC News, noting Gallant came back from his trip to the U.S. and gave a "directive: 'We need to make an immediate impact on the scope and speed of the humanitarian aid going into Gaza,' and that's what we've done."

-ABC News' Matt Gutman

U.S. officials are skeptical that Hamas is holding enough Israeli hostages to meet the requirements for the first phase of the proposed deal currently on the table, according to a source familiar with the negotiations.

The proposal calls for Hamas to hand over 40 hostages who are either: children; women not affiliated with the Israel Defense Forces; sick adults; or adults over 50 years old, according to the officials.

In exchange, Israel would free an undefined number of Palestinian prisoners and implement a cease-fire of at least six weeks.

-ABC News’ Shannon Crawford

World Central Kitchen said one of its workers was injured in a separate airstrike in Gaza on the same day that seven WCK workers were killed.

Fifteen minutes before the Israeli attack that killed seven workers on April 1, "One of our brave Palestinian staff members was gravely injured in a reportedly deadly airstrike at al-Bashir Mosque in Deir al-Balah," World Central Kitchen said in a statement.

The two attacks were within miles of each other, WCK said.

The Palestinian staff member, Amro, suffered "serious head and hand injuries while he was off duty in a home close to the mosque in the area surrounding our warehouse and newly established kitchen in Deir al-Balah," WCK said.

He was in a coma for some time and is now recovering, the agency said.

"Amro joined the WCK team just after the start of the year," WCK said. "He was given rare opportunities to leave Gaza for Egypt several times, but he refused. He always says, 'I am here serving people hot food every day. I will not leave my job and let them suffer.'"

Sources at the White House say there’s deep concern that an Iranian retaliatory strike against Israel -- and the possible Israeli response -- will widen this war.

President Joe Biden cut his weekend vacation short to consult with his national security team in preparation for this. They’ve been on high alert and knew this attack was imminent.

U.S. officials the military is prepared to provide assistance to defend Israel against attacks if needed.

The U.S. is already moving military assets to the region to deter Iran and help protect U.S. forces. Officials say they have been urging Iran against further escalation or attacks on U.S. forces. They’ve been stressing that the U.S. was not involved in the Damascus, Syria, strike earlier this month.

-ABC News' Selina Wang