French Foreign Minister Jean-Marc Ayrault called Monday for "sanctions against those who put obstacles in the way, against those who ultimately stop the Libyan authorities from starting their work."
The EU is drawing up a small list of "spoilers" to be targeted by sanctions.
Unconfirmed reports suggest Nouri Abu-Sahmain, head of the Tripoli parliament, and Khalifa Ghweil, prime minister of the Tripoli Salvation government, are in the EU's sights, AP reported.
Libya has been split between rival governments since 2014, a consequence of the chaos that engulfed the country after a 2011 uprising that toppled and killed longtime dictator Moammar Gadhafi.