President Donald Trump's son-in-law Jared Kushner has been a promoter of Saudi Prince Mohammed bin Salman since the early days of the administration and recently offered the prince advice on how to handle the outrage over the slaying of Washington Post columnist Jamal Khashoggi, The New York Times reported Saturday.

Kushner, 37, who serves as Trump's adviser on the Middle East, has kept up informal conversations with the prince, 33, since early 2017, the Times reported, citing unnamed sources. Three former senior officials told the paper that the politically inexperienced Kushner's private chats with Mohammed could have made him "susceptible to Saudi manipulation."

Khashoggi was killed on Oct. 2 by Saudi agents at the country's consulate in Istanbul. Although the administration has played down reported evidence linking the slaying to the prince and cautioned lawmakers not to take action against Saudi Arabia in response to the killing, senators say U.S. intelligence reports clearly implicate the crown prince.

"I think he’s complicit to the highest level possible," said Sen. Lindsey Graham, R-S.C., after a CIA briefing last week on Khashoggi's death, which included the use of a bone saw. "There’s not a smoking gun. There’s a smoking saw."

After the killing, Kushner "became the prince’s most important defender inside the White House," the Times reported.

The White House acknowledged one call after the slaying. On Oct. 10, Kushner and national security adviser John Bolton spoke with the prince and encouraged the Saudis to be "transparent in the investigation process," White House spokeswoman Sarah Sanders said in a statement.

But the Times reported that Kushner's informal talks with Mohammed continued. Citing an unnamed Saudi source, the paper said, "Kushner has offered the crown prince advice about how to weather the storm, urging him to resolve his conflicts around the region and avoid further embarrassments."

In October, CNN reported that Kushner's private chats with the prince were causing concern among national security officials who "worried off-the-books conversations with the young prince could lead to misunderstandings or worse."

CNN also reported that Kushner and Mohammed often sent each other texts via WhatsApp.

The Times reported Kushner's relationship with Mohammed began after aides to the prince, often referred to by his initials MBS, met with Kushner in November 2016, just after Trump won the election. According to a slideshow the Saudi officials put together to report on the meeting, "Kushner made clear his lack of familiarity with the history of Saudi-American relations" and he "expressed his satisfaction with what was explained about the Saudi role in fighting terrorism."

The delegation presented ideas they thought would appeal to Trump, according to the slideshow obtained by the Lebanese newspaper AlAkhbar and translated by the Times. Those proposals included intelligence sharing, a joint center to combat extremist ideology, the establishment of an "Arab NATO," and increased Saudi spending on U.S. defense contracts and investment in the U.S.

The White House did not immediately respond to USA TODAY's request for comment on the Times' story.

"Jared has always meticulously followed protocols and guidelines regarding the relationship with MBS and all of the other foreign officials with whom he interacts," a White House spokesperson told the Times in a statement.

White House officials told the Times that there was nothing unusual about Kushner's ties with the prince. They said he has relationships with many important figures in the Middle East and that representatives of previous administrations were also closely tied to Saudi government officials.

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