Earlier this week, long-time Fox News anchor Megyn Kelly announced she’d be leaving cable news for a gig at NBC’s news desk.

Sources told Page Six that the “notoriously territorial” Matt Lauer “blew a gasket” when he learned Kelly would be his co-worker:

The negotiations over Megyn Kelly’s move to NBC were so secretive that only a handful of the network’s top-tier talent was let in on the news just before it was announced to the public.

We’re told that even the notoriously territorial Matt Lauer and just-renewed “Today” show figurehead Savannah Guthrie were only told about their high-profile new colleague on the morning that the story broke.

Sources said Lauer “blew a gasket,” which NBC insiders deny.

Also given the heads-up were MSNBC’s “Meet the Press” anchor Chuck Todd and “NBC Nightly News” anchor Lester Holt.

Other staff found out when it hit the wires.

Kelly wants to spend more time with her children and was looking for a schedule more conducive to family time.

No word yet on who will replace her primetime spot, but there’s plenty of speculation.

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