The Israeli Defense Forces issued a new statement in English calling the Israeli military’s strikes that killed seven World Central Kitchen aid workers on Monday a "tragedy."

"It was a terrible chain of errors and it should never have happened," the IDF said. "The IDF takes full responsibility for this regrettable loss of life."

The IDF said earlier that the airstrike came after Israeli forces misidentified a WCK worker in the convoy as a Hamas gunman.

The IDF said WCK correctly coordinated its movements with the IDF prior to the night the workers were killed and that there was a "comprehensive plan" in place for the WCK workers’ movements on Monday.

-ABC News’ Ellie Kaufman

U.S. officials are reviewing Israel's report on the Israel military’s attack on World Central Kitchen aid workers "very carefully" and "will be discussing its conclusions with Israeli officials and with humanitarian organizations in the days to come," Secretary of State Antony Blinken told reporters.

The Israel Defense Forces said its airstrike in Gaza that killed seven WCK aid workers on Monday came after Israeli forces misidentified a WCK worker in the convoy as a Hamas gunman.

Blinken said Israeli Prime Minister Benjamin Netanyahu "indicated" to President Joe Biden in their Thursday call "that Israel would be making further changes to its procedures to make sure that those who are providing assistance to people who so desperately need it in Gaza are protected."

"It's very important that Israel is taking full responsibility for this incident. It's also important that it appears to be taking steps to hold those responsible accountable," Blinken said. "Even more important is making sure that steps are taken going forward to ensure that something like this can never happen again."

Blinken said the U.S. would be "looking to see not just what steps are being taken, but the results that follow" from potential changes to Israeli military operations.

-ABC News’ Chris Boccia

White House national security communications adviser John Kirby warned Friday that if the U.S. doesn’t "start seeing meaningful changes in the way Israel is prosecuting these [military] operations [in Gaza] and allowing for humanitarian assistance [in Gaza], and working toward a hostage deal and cease-fire, then we’re going to have to make changes in our Gaza policy."

In his interview with ABC News' "Good Morning America," Kirby would not say if those changes in Gaza policy would mean conditioning U.S. aid.

But Kirby said President Joe Biden was very clear on his call Thursday with Israeli Prime Minister Benjamin Netanyahu that the U.S. must "see some changes."

"We’ve got to see the humanitarian situation improve in Gaza, or otherwise we will have to try to take a look at our own policy and make decisions, and change the way that we’re supporting Israel," Kirby said.

The U.S. still wants an immediate cease-fire in exchange for the release of the Israeli hostages and for getting more aid into Gaza, Kirby stressed. U.S. officials will be among the negotiators meeting this weekend in Cairo, he said.

Israel Defense Forces released a statement Friday about the deadly airstrike in Gaza that killed seven World Central Kitchen aid workers on April 1.

The IDF said it misidentified a WCK worker in the convoy as a Hamas gunman.

"After the vehicles left the warehouse where the aid had been unloaded, one of the commanders mistakenly assumed that the gunmen were located inside the accompanying vehicles and that these were Hamas terrorists. The forces did not identify the vehicles in question as being associated with WCK," the IDF said in a statement Friday.

"Following a misidentification by the forces, the forces targeted the three WCK vehicles based on the misclassification of the event and misidentification of the vehicles as having Hamas operatives inside them, with the resulting strike leading to the deaths of seven innocent humanitarian aid workers," the statement continued.

The report said there were three strikes on the convoy. It also said WCK workers hit in the first vehicle were hit again while moving to another vehicle in the convoy.

"The investigation's findings indicate that the incident should not have occurred. Those who approved the strike were convinced that they were targeting armed Hamas operatives and not WCK employees," the IDF said. "The strike on the aid vehicles is a grave mistake stemming from a serious failure due to a mistaken identification, errors in decision-making, and an attack contrary to the Standard Operating Procedures."

It said WCK correctly coordinated its movements with the IDF prior to the night the workers were killed and that there was a "comprehensive plan" in place for the WCK movement on April 1.

The U.S. is sanctioning two groups and 16 people it says enabled Iran's drone production following Iran's attack on Israel last weekend.

"Today, in coordination with the United Kingdom and in consultation with partners and allies, we are taking swift and decisive action to respond to Iran’s unprecedented attack on Israel," Treasury Secretary Janet Yellen said. "We’re using Treasury’s economic tools to degrade and disrupt key aspects of Iran’s malign activity, including its UAV program and the revenue the regime generates to support its terrorism."

The Treasury Department said it’s sanctioning Khuzestan Steel Company, Iran's largest steel producer. The Treasury Department said Iran's metals sector generates "several billion dollars in revenue annually."

The U.S. is also targeting the Iranian carmaker Bahman Group for its role in making vehicles used by the Islamic Revolutionary Guard Corps for military operations.

The sanctions also target people who work for Iran-based drone manufacturers, including executives of the Mado Company, which the U.S. says produced drone engines used in Iran's Shahed UAVs. The U.S. also sanctioned members of the IRGC who it says help supply proxy groups, like the Houthis in Yemen, with drones that have attacked U.S. service members in the Red Sea.

Yellen added that the U.S. would "continue to deploy" sanctions to counter any further action by Iran, with the goal of making it harder and more expensive for Iran to undertake destabilizing actions.

President Joe Biden said in a statement that these sanctions are "holding Iran accountable."

Biden emphasized that the sanctions are in coordination with the international community, and he said the other G7 countries are committed to increasing "economic pressure" on Iran alongside the U.S.

Biden said he has instructed his team to continue to impose sanctions that will degrade Iran's military capabilities.

Biden also reiterated his ironclad support for Israel, and issued a warning to Iran and those who "enable" Iran's attacks.

"We are committed to the security of our personnel and partners in the region," Biden said. "And we will not hesitate to take all necessary action to hold you accountable."

-ABC News’ Michelle Stoddart and Justin Gomez