There's been speculation that Mark Zuckerberg wants to run for office one day, but he has denied it. Thomson Reuters

President Trump, Vice President Mike Pence, and other members of the White House will meet with executives from the biggest tech companies on Monday to discuss modernizing the government.

And out of the nearly 20 companies scheduled to attend, one glaring absence is Facebook.

Neither CEO Mark Zuckerberg nor COO Sheryl Sandberg will be at the meeting, a Facebook spokesperson confirmed to Business Insider, citing scheduling conflicts as the reason why.

Sandberg's absence makes sense given that the biggest advertising festival in the world, Cannes Lions, is currently underway in the south of France. But Zuckerberg's absence is more notable, especially given that he also skipped Trump's last meeting with tech executives in December.

Zuckerberg is scheduled to speak at a Facebook event in Chicago on Thursday, so there's a chance he's busy preparing for that. He's also spoken with Trump multiple times by phone since the election, as Business Insider previously reported.

Facebook board member and Trump advisor Peter Thiel will also be in attendance, representing his investment firm Founders Fund.

Even still, it's odd for Zuckerberg, a tech expert and billionaire philanthropist, to not be in the room for a meeting about how the government can bring its technical chops into the 21st century. The group will also discuss Trump's planned overhaul of the country's visa program for highly-skilled workers, which Facebook and other tech companies rely heavily upon to hire employees.

Here's the full list of tech executives scheduled to meet with the White House on Monday: