The announcement was immediately rejected by Israeli Defense Minister Benny Gantz.
Al-Khatib said Al Jazeera journalist was fleeing the direction of the shot when the 5.56mm bullet hit her in the head, causing a tear in her brain tissue and killing her.
The bullet contained a fragment of iron used in special ammunition that penetrated armor, Al-Khatib said.
The autopsy was performed at the Institute of Forensic Medicine at Al Najah University in Nablus.
Both the Palestinian Authority and Al Jazeera have accused the Israeli army of intentionally killing Abu Akleh while covering an Israeli military raid on Jenin on May 11.
A CNN investigation released Tuesday also suggested that Abu Akleh was the target of the Israeli Defense Forces, based on eyewitnesses, an audio forensic analyst and an explosives weapons expert.
But IDF says it is unclear who killed Abu Akleh, arguing that she was shot by Palestinian militants firing indiscriminately or by IDF troops returning fire. IDF says they are investigating, but they need the bullet that killed her to determine who fired the deadly shot.
Gantz on Thursday called on Palestinian Authority investigators to “deliver the bullet and all its findings.” He reiterated Israel’s willingness to cooperate in an international investigation, a prospect that the Palestinian Authority has repeatedly ruled out, saying they do not trust Israel.
Gantz also appeared to be referring to CNN’s investigation, accusing it of promoting “false assessments.”
“Any claim that IDF intentionally harms journalists or civilians not involved is a blatant lie,” he said.
Al-Khatib said on Thursday that the bullet that killed Abu Akleh would not be handed over to the Israeli army for investigation.
“Israel ordered the bullet even before we started the investigation. This shows that they were trying to deceive us and the whole world,” Al-Khatib told reporters. “We’ll never give them the bullet.”