White House national security spokesman John Kirby said on Sunday that reforms by Israel after its deadly strike on an aid convoy in Gaza last week have to be verified over time to restore "confidence."
Seven workers with the World Central Kitchen, or WCK, were killed in the attack, which Israel has described as a "terrible" mistake.
The Israeli government and military took some notable steps in response, including allowing more aid into Gaza and disciplining officers.
"We need to see change over time," Kirby told ABC News "This Week" co-anchor Martha Raddatz. "So, these announcements, Martha, they're very welcomed and they're good. And they are some of the things that the president asked specifically for Prime Minister [Benjamin] Netanyahu to do in terms of opening up additional crossings, allowing more trucks in, getting the deconfliction process in place."
"But now we have to judge it over time, we have to see past the announcements and see if they actually meet these commitments over time, in a sustained and verifiable way, so that confidence can be restored not just between aid workers and [Israel's forces], but between the people of Gaza and Israel," Kirby continued.
Initially staunchly supportive of Israel after the Oct. 7 terrorist attack by Hamas that sparked the current war, President Joe Biden has grown more vocally critical of Israel's military campaign in Gaza -- including pressing Netanyahu last week after the strike on the WCK workers.
Israeli officials have repeatedly defended their military operations in Gaza, insisting they take steps to curb civilian deaths while allowing aid to flow in that cannot benefit Hamas.
In a move hailed by the White House, Netanyahu last week allowed for more aid to flow into Gaza after a conversation with Biden in which the president voiced his outrage over civilian deaths in Gaza.
"This increased aid will prevent a humanitarian crisis and is necessary to ensure the continuation of the fighting and to achieve the goals of the war," an Israeli official told ABC News last week.
On Friday, the Israeli military released a report on its investigation into how the WCK strike occurred -- finding that the decision to hit the aid convoy was a "serious violation" of their rules and noting that the team that carried it out lacked sufficient evidence to do so, twice violating operating rules.
In response, the Israel Defense Forces said they dismissed two officers, suspended two commanders and reprimanded three others.
"This is a tragedy. It was a terrible chain of errors, and it should never have happened. The IDF takes full responsibility for this regrettable loss of life," an Israeli military spokesman told reporters on Friday.
Chef José Andrés, who founded WCK, has lambasted the conduct of Israel's forces in Gaza as they pursue Hamas fighters and he has called for an outside investigation of the strike.
Kirby on Sunday reiterated the White House's condolences for the WCK deaths, saying, "The president shares that grief and sorrow."
Pressed by Raddatz on whether he also wants an independent investigation, Kirby said the administration is examining the results of Israel's probe.
"We're looking at the investigation right now, Martha. We haven't come to any conclusions one way or another. This was an investigation that was done sort of akin to like an inspector general. So, it was outside the chain of command. But again, we're working our way through that," he said.
He declined to weigh in on the Israel military's claim that because it was night, the WCK branding on the top of the vehicles wasn't visible to drone operators just before the strike last week, which Andrés disputes.
"There were white cars. That logo is very colorful. Even in a dark night, I guarantee you that those drones could be seen," Andrés said in a separate interview with Raddatz.
More broadly, Raddatz asked Kirby if Israel's forces were following "legitimate rules of engagement" in destroying three vehicles after claiming that at one point they saw a suspected gunman in the convoy.
"I think again, we're gonna have to work our way through this investigation and the decision-making process that goes in -- not just one, but then three strikes and what the intelligence was telling them, at least what they believed it was," Kirby said.
"We know from our own experience that the intelligence you get and you process and you analyze may not always be accurate, and you act on that intelligence," he said.
"I don't want to sound like a broken record, but what really matters is they make the deconfliction changes [to reduce mistakes] and the communication changes so that this doesn't happen again," Kirby said.
Aid groups like WCK could well curtail their work in Gaza, compounding the humanitarian problems there, in light of the Israeli strike, Kirby said.
"We've got to make sure that they feel safe and secure getting into Gaza and distributing that aid," he said.
Overall, while the president and top administration officials have increasingly warned of potential consequences if Israel doesn't shift its approach to civilians in Gaza, Kirby declined to preview what some of those actions could be, saying he didn't want to get out ahead of Biden "or close down his decision space" when pressed by Raddatz.
However, Kirby indicated that the U.S. will continue to be a major partner in supplying military support to Israel for its defensive needs.
"Israel has a right to defend itself and I think it's important to also remember, they live in a tough neighborhood. We're all focused on the fight in Gaza as we rightly should be. But they're facing threats from Iran and from Iran-backed groups all through the region. We've got to make sure that they're ready for this," he said.
Raddatz highlighted a timeline of growing casualties in Gaza alongside America's growing criticism of Israel's tactics.
"So why do you think anything will change?" she asked Kirby.
"I'm glad you brought that timeline up because it shows the degree, the growing degree, of frustration that we've had with the way these operations are being prosecuted and the way that the Israelis are acting on the ground in terms of civilian casualties," Kirby insisted. "So we have been increasingly frustrated."
ABC News' Julia Cherner, Meredith Deliso, Meghan Mistry and Dana Savir contributed to this report.