"Secretary Austin expressed his outrage at the Israeli strike on a World Central Kitchen humanitarian aid convoy that killed seven aid workers, including an American citizen," Ryder said on Wednesday.
He added that "Secretary Austin stressed the need to immediately take concrete steps to protect aid workers and Palestinian civilians in Gaza after repeated coordination failures with foreign aid groups."
The US and Israeli defense chiefs will conduct a "swift and transparent" investigation into the incident and share conclusions publicly, as well as "hold those responsible to account," the release said.
"Secretary Austin stated that this tragedy reinforced the expressed concern over a potential Israeli military operation in Rafah, specifically focusing on the need to ensure the evacuation of Palestinian civilians and the flow of humanitarian aid," the spokesperson said.
Austin also reiterated US support for "Israel's defense against a range of regional threats," the release said.
On Monday, WCK staff were traveling "in a deconflicted zone" in two armored cars branded with the organization's logo and a soft-skin vehicle, the NGO said. The humanitarian convoy was attacked as it left the Deir al Balah warehouse, where the team had unloaded more than 100 tonnes of food aid brought to Gaza by sea. The organization said that its convoy had coordinated its movements with the IDF.
The Israeli strike against the staff of the WCK killed seven employees from Australia, Poland, the United Kingdom, and Palestine, as well as a dual citizen of the United States and Canada. The organization suspended its operations in the Gaza Strip after the deadly incident.