Apple's Tim Cook, Amazon's Jeff Bezos, Microsoft's Satya Nadella, Alphabet's Eric Schmidt and IBM's Ginni Rometty are among those expected to attend the meeting.
The French capital remains on high alert after several attacks on police forces and civilians in the last two years.
Fire departments in the United States and United Kingdom are increasingly using unmanned aircraft.
The attorney general spoke for the first time publicly about the firing of FBI Director James Comey.
Newsmax CEO Christopher Ruddy had claimed Trump was considering firing Mueller.
The president made the comment during an unrelated press conference with Romanian President Klaus Iohannis.
The website for Columbia Law School professor Daniel Richman says he "is currently an adviser to FBI Director James B. Comey."
The former FBI director will speak about his interactions with Trump, including how the president demanded loyalty and made other requests.
The Senate Intelligence Committee published the former FBI director's opening statement a day before he is scheduled to testify.
The NSA director and National Intelligence Director Dan Coats responded to media reports that Trump had tried to interfere with the FBI's Russia investigation.
The former FBI director is scheduled to testify before the Senate Intelligence Committee on Thursday.
Katy Perry, Miley Cyrus, Pharrell, Take That, Usher and Niall Horan will also perform at the concert, which will benefit the Manchester Emergency Fund.
The pop singer and actress says she plans to return to Manchester for a benefit concert that will raise money for the victims and their families.
The internet entrepreneur, who is fighting extradition to the U.S., claims Rich contacted him as early as 2014 and was involved in the DNC leaks.
Brennan has said he doesn't think President Trump "has a full appreciation of Russian capabilities."
A tweet from the embassy comes days after a report that suggested Rich was a WikiLeaks informant, which has since been refuted.
The special counsel was known at the FBI for being strong-willed, with a very different leadership style to James Comey, sources tell Newsweek.
To fill appointments, Trump keeps turning to the law firm Kasowitz, Benson, Torres and Friedman, which has represented him for years.
Citing an unnamed "federal investigator," a Fox News report suggested that Rich gave 44,000 Democratic National Committee emails to WikiLeaks.