'American Idol' Wants Lionel Richie + Charlie Puth As Final Two Judges

(TMZ) -- American Idol is getting closer to assembling a full squad -- the show's zeroing in on finalists to join Katy Perry on the judges' panel.

Idol sources tell TMZ ... Lionel Richie's still a favorite to fill one of the two remaining seats, and singer Charlie Puth has emerged as a front-runner for the other one. TMZ was told show execs will meet with ABC this week to finalize their choices and make offers.

There could be a country curveball, though ... TMZ sources say Luke Bryan is in the mix because he impressed producers in early discussions. Also, if things don't work out with two of those three ... TMZ was told Keith Urban is an 'Idol' vet who could slide in as an alternate.

Katy and Ryan are anxiously waiting to see who joins 'em.

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