ISTANBUL — Saudi journalist Jamal Khashoggi was strangled as soon as he entered the Saudi consulate in Istanbul as part of a premeditated killing and his body was dismembered before it was removed, a top Turkish prosecutor said Wednesday.

Chief Istanbul prosecutor Irfan Fidan’s office also said in a statement that discussions with Saudi chief prosecutor Saud al-Mojeb over the killing yielded “no concrete result” despite Turkey’s “good-intentioned efforts to reveal the truth.”

The statement was the first public confirmation by a Turkish official that Khashoggi was strangled and mutilated after he entered the Saudi Consulate on 2 October. It also pointed to a lack of cooperation from Saudi officials in the investigation of the slaying.

“In accordance with plans made in advance, the victim, Jamal Khashoggi, was strangled and killed immediately after entering the Consulate General of Saudi Arabia,” the prosecutor’s office said.

“The victim Jamal Khashoggi’s body was dismembered and destroyed following his death by suffocation, again in line with the advance plans,” the two-page statement read.

On Wednesday, US President Donald Trump said he doesn’t feel “betrayed” by Saudi Arabia over Khashoggi’s death.