(CNN) - Amazon CEO Jeff Bezos is scheduled to meet with federal prosecutors in New York as soon as this week, according to people familiar with the matter. The meeting signals that the US attorney's office is escalating its inquiry connected to Bezos's suggestion that the kingdom of Saudi Arabia was behind a National Enquirer story that exposed his extramarital affair and his claim that the tabloid attempted to extort him.
Plans for that meeting come as prosecutors in the Southern District of New York are seeking to obtain access to Bezos's electronic devices, these people said. They are attempting to examine Bezos's private investigators' allegation that the Saudis "gained private information" from his phone, and that such information wound up in the hands of American Media Inc. tabloid the National Enquirer, which published Bezos's texts.
Attorneys for Bezos, the world's richest man, have been engaged in negotiations regarding his electronics. In recent weeks, Bezos's attorneys and investigators turned over to federal authorities documents and other material from their own inquiry, but not his devices, these people said.
Bezos has suggested he became a target of the Saudis due to his ownership of The Washington Post and its coverage of the murder of its columnist Jamal Khashoggi.
Amid these developments, Bezos has expanded his legal team, adding attorney Matthew Schwartz, a partner at law firm Boies Schiller Flexner LLP who spent a decade as a federal prosecutor in New York, the people familiar with the matter said.
Schwartz didn't immediately respond to a request for comment. A spokeswoman for the US attorney's office declined to comment. A spokesman for the FBI declined to comment.
It's not clear whether federal prosecutors have independent evidence to corroborate the claim that the Saudis hacked Bezos's phone or had any connection to the National Enquirer's story on his affair.
Since February, prosecutors have been examining Bezos's claim that the publisher attempted to extort him after he sought to determine how the National Enquirer gained access to private texts he exchanged with a woman named Lauren Sanchez, with whom he was having an extramarital affair.
Prosecutors have been probing the extortion claim in part to determine whether the actions of the National Enquirer's publisher, American Media, violated a non-prosecution agreement it struck last year with prosecutors. As part of that agreement, company officials admitted to its involvement in a hush-money scheme to influence the 2016 presidential election by silencing a woman who claimed an affair with then-candidate Donald Trump and agreed not to commit any crimes for three years.
The agreement stemmed from prosecutors' investigation of Trump's former personal attorney Michael Cohen, who helped orchestrate that hush-money payment.
Prosecutors haven't reached a determination concerning the extortion claim, according to a person familiar with the investigation, and they are now working to examine another set of claims -- those made last month by Bezos's security consultant, Gavin de Becker.
"Our investigators and several experts concluded with high confidence that the Saudis had access to Bezos' phone, and gained private information," de Becker wrote in an opinion article in the Daily Beast. "As of today, it is unclear to what degree, if any, AMI was aware of the details."
De Becker wrote that while his investigation found that AMI had paid Sanchez's brother, Michael Sanchez, for the information on Bezos, the Saudis were the original source of at least some of the material.
Bezos himself had suggested in his own online post that he had become the enemy of Saudi Arabia and Trump due to coverage of the murder of Khashoggi in the Washington Post, and pointed out that AMI had long sought to ingratiate itself with both the kingdom and the President.
A spokesman for the publisher has said "American Media does not have, nor have we ever had, any editorial or financial ties to Saudi Arabia."
Following the publication of de Becker's op-ed, the publisher issued a statement saying Sanchez alone was the source for its reporting. "Despite the false and unsubstantiated claims of Mr. de Becker, American Media has, and continues to, refute the claims that the materials for our report were acquired with the help of anyone other than the single source who first brought them to us," the company said. "There was no involvement by any other third party whatsoever."
An attorney for AMI CEO David Pecker, Elkan Abramowitz, said in February that the source for the tabloid's story was "not Saudi Arabia."
Adel al-Jubeir, Saudi Arabia's former minister for foreign affairs, told CBS News that the government had "nothing to do with" the matter.
Though de Becker wrote that the results of his investigation had been turned over to federal officials, it is standard practice for prosecutors to conduct their own examination of such allegations, and, in the case of a hacking claim, to seek first-hand access to the electronics that were allegedly compromised.
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