NBC is making major changes to its top-rated Today morning show to accommodate the arrival of former Fox News star Megyn Kelly, according to a report.

Sources close to the network told the New York’s Post‘s Page Six that Kelly — who announced she would join NBC this month after more than a decade at Fox — is expected to take over either the 9 a.m. Today hour, currently hosted by Tamron Hall and Al Roker, or else the 10 a.m. hour, currently hosted by Hoda Kotb and Kathie Lee Gifford.

An insider told the paper that staffers at the network are upset that NBC would make significant changes to its Today lineup, given the show’s strong ratings over the last several months. Today producers were reportedly informed of the changes Friday morning, one day after Al Roker tweeted a celebratory message about the show’s ratings.

“People are pissed. The third hour was beating every syndicated show across the board,” the insider told Page Six. “They were in over their head and bit off more than they can chew when they hired Megyn.”

Another insider told the paper that “everyone has been left in the dark” regarding the changes.

Page Six also reported that Hall is expected to leave NBC next month when her contract expires.

Kelly turned down a reported $100 million, four-year offer to remain at Fox News to jump to NBC, where she is set to headline both a daytime news show and a Sunday night “in-depth” newsmagazine show.

In the absence of The Kelly File, Fox News moved Tucker Carlson into Kelly’s old 9 p.m. primetime slot and gave Martha McCallum the 7 p.m. slot with a new show, The First 100 Days.

In its first two weeks, Tucker Carlson Tonight has averaged nearly double the ratings for The Kelly File over the same time period last year in the advertiser-coveted 25-54 demographic.

Follow Daniel Nussbaum on Twitter: @dznussbaum