Maranello, November 29 - Motor-racing's governing body FIA said Thursday that Sebastian Vettel did not carry out an illegal overtaking move at Sunday's Brazilian Grand Prix when the German clinched the Formula One world title. Ferrari said earlier Thursday that they were asking FIA for clarification after footage from Vettel's on-board camera appeared on the Internet that seemed to show the Red Bull driver overtaking Jean-Eric Vergne, of sister team Toro Rosso, under yellow flags - which ban such moves. Vettel came sixth in Brazil to clinch his third world title, finishing the championship just three points ahead of Ferrari's Fernando Alonso, who came second on Sunday. FIA sources told motorsport magazine Autosport's website that there was "no case" to answer and that Vettel's pass was legitimate. The sources said the yellow-flag sector ended about 150m before the turn at Sao Paulo's Interlagos circuit where the move took place.