WASHINGTON — Shortly after journalist Jamal Khashoggi was assassinated last month, a member of the kill team instructed a superior over the phone to “tell your boss,” believed to be Crown Prince Mohammed bin Salman of Saudi Arabia, that the operatives had carried out their mission, according to three people familiar with a recording of Khashoggi’s killing collected by Turkish intelligence.

The recording, shared last month with CIA Director Gina Haspel, is seen by intelligence officials as some of the strongest evidence linking Crown Prince Mohammed to the killing of Khashoggi, a Virginia resident and Washington Post columnist whose death prompted an international outcry.

While he was not mentioned by name, U.S. intelligence officials believe “your boss” was a reference to Crown Prince Mohammed. Maher Abdulaziz Mutreb, one of 15 Saudis dispatched to Istanbul to confront Khashoggi at the Saudi Consolate there, made the phone call and spoke in Arabic, the people said.

Turkish intelligence officers have told U.S. officials they believe that Mutreb, a security officer who frequently traveled with Crown Prince Mohammed, was speaking to one of the crown prince’s aides. While translations of the Arabic may differ, the people briefed on the call said Mutreb also said to the aide words to the effect of “the deed was done.”

“A phone call like that is about as close to a smoking gun as you are going to get,” said Bruce O. Riedel, a former CIA officer now at the Brookings Institution. “It is pretty incriminating evidence.”

Turkish officials have said that the audio does not conclusively implicate Crown Prince Mohammed, and U.S. intelligence and other government officials have cautioned that however compelling the recording may be, it is still not irrefutable evidence of his involvement in the death of Khashoggi.

Even if Mutreb believed the killing was ordered by the crown prince, for example, he may have had an inaccurate understanding of the origins of the order. Crown Prince Mohammed is not specifically named on the recording, and intelligence officials do not have ironclad certainty that Mutreb was referring to him.

In a statement today, Saudi officials denied that the crown prince “had any knowledge whatsoever” of Khashoggi’s killing. Referring to Mutreb’s instructions to “tell your boss,” the Saudi statement said that Turkey had “allowed our intelligence services to hear recordings, and at no moment was there any reference to the mentioned phrase in the such recordings.”

The Turks may possess multiple recordings, including surveillance of telephone calls, and Turkish authorities may have shared the audio only selectively.

A CIA spokesman declined to comment.

The call was part of a recording that Turkish officials played for Haspel during her visit in October to Ankara, Turkey’s capital, but they did not allow her to bring it back to the United States. On Saturday, President Recep Tayyip Erdogan of Turkey announced that his government had shared the audio with Saudi Arabia, the United States and other Western allies.

But while Turkish officials have played the recording for U.S. and other intelligence agencies and provided transcripts, the Turks have not handed over the recording for independent analysis, according to Turkish officials.

Turkey shared evidence from the case with “a large number of friendly nations,” a spokesman for Erdogan, Fahrettin Altun, said today. Reacting to French criticism of Turkey’s handling of the case, Altun said that the Turkish government had played an audio recording for French intelligence officials and given them transcripts.

“Let us not forget that this case would have been already covered up had it not been for Turkey’s determined efforts,” Altun said.

The growing evidence that Crown Prince Mohammed was involved in the killing of Khashoggi is certain to intensify pressure on the White House, which appeared intent on relying on a lack of concrete proof of his involvement to preserve its relationship with him. The crown prince has fostered a close relationship with the president’s son-in-law and senior adviser, Jared Kushner, and the Trump administration has turned Saudi Arabia into Washington’s most crucial Arab partner.

Some Trump advisers have argued that they would need indisputable evidence of Crown Prince Mohammed’s involvement in Khashoggi’s killing before they would punish him or the kingdom more harshly. Turkish officials have said the recording contains evidence of a premeditated killing, in which Saudi agents quickly strangled Khashoggi and methodically dismembered his body with a bone saw.

The administration, according to current and former officials, is hoping that making some modest moves on sanctions and curtailing support for the Saudi war effort in Yemen will satisfy critics, including those on Capitol Hill.

But the shift in power in Congress, where Democrats take control of the House in January, is also increasing pressure on the administration to take more punitive action. The CIA and other intelligence officials were set to brief Congress this week, and congressional leaders will press Haspel for her assessment of Crown Prince Mohammed’s culpability.