WASHINGTON — More than two months after an Israeli airstrike killed seven World Central Kitchen aid workers in Gaza, the Biden administration still has not provided an assessment of the preliminary investigation by Israel that determined the incident was a “grave mistake.”

White House officials have privately said for weeks that they are waiting on Israel to provide “underlying information” about the April strike and cannot complete its review without it. A meeting with Israeli officials about the additional details the U.S. has requested is supposed to take place sometime in the next couple weeks, but no date has been set, according to two U.S. officials familiar with the discussions.

“We continue to engage with the Israeli government on this,” one of the officials told NBC News.

The Israel Defense Forces released an initial assessment a few days after the April 1 strike that found that the attack “should not have occurred” and said those who approved the action “were convinced that they were targeting armed Hamas operatives and not WCK employees.” The IDF continues to examine what happened and will submit an additional investigation for review, the IDF said in a statement.

The delay by the Biden administration in making an assessment on Israel’s investigation of the WCK strike comes as the U.S. is again deferring to Israel about another deadly incident in Gaza — an airstrike that killed dozens of Palestinian civilians in a tent camp in Rafah late last month.

“Let’s see what the investigation comes up with,” White House National Security Council spokesperson John Kirby told reporters at the time. The White House has not said how long that investigation may take.

In the aftermath of the strike on WCK aid workers, the group called for an independent inquiry into the deadly attack.

“We demand the creation of an independent commission to investigate the killings of our WCK colleagues,” WCK said in a statement on April 5. “The IDF cannot credibly investigate its own failure in Gaza.”

The Biden administration has not endorsed an independent investigation, instead officials have said its own assessment of Israel’s inquiry needs to be completed first. Administration officials have been quick to point out that Israel made some adjustments to its rules of operation based on the findings from its investigation into the WCK strike.

“Israel did conduct an investigation and presented those findings publicly, and then made changes in response to those findings, which we thought it was very important that they do,” State Department spokesperson Matt Miller said last month.

Following the April strike, President Joe Biden threatened to condition support to Israel if it failed to take concrete steps toward better protecting aid workers and innocent civilians. He conveyed that message in a phone call with Israeli Prime Minister Benjamin Netanyahu, during which Biden “made clear that U.S. policy with respect to Gaza will be determined by our assessment of Israel’s immediate action on these steps.”

One of the seven WCK employees killed in the April 1 attack, Jacob Flickinger, was a dual American and Canadian citizen. Others were from Britain, Australia and Poland, along with a Palestinian driver. Biden said at the time that he was “outraged” by their deaths.

This week, WCK founder Jose Andres was honored for his humanitarian efforts at a Washington Gala to raise money for the United Nations refugee agency, where he gave an emotional appeal for a cease-fire in Gaza.

Andres choked up when reciting the names of his seven co-workers killed in the attack. He noted that the aid group was the first to respond with food in Israel for survivors of the Oct. 7 attack by Hamas and has been working in Gaza to help the victims of the ongoing war.

After his remarks, Andres told NBC News that the number of aid trucks getting into Gaza are only a fraction of what is needed.

Biden vowed in his State of the Union address in March to set up a temporary pier off the coast of Gaza for the U.S. military to assist in getting more humanitarian aid to Palestinians. Pallets were transferred to the shore last month for several weeks before being derailed by rough weather, which halted the project completely.

The pier was reattached to the beach in Gaza on Friday, according to U.S. Central Command, and the Biden administration expects aid deliveries to resume in the coming days. The goal will be to move 500,000 pounds over the beach daily initially and then grow that over time, administration officials have said.