Formula One's governing body on Saturday ruled out a deeper investigation of Red Bull's ride-height device while recognising it could not be sure there had been no breach of the rules in the past.

Red Bull faced scrutiny over suspected ride height adjustments ahead of the US GP. An FIA investigation cleared them, but lingering questions keep the paddock buzzing.

Zak Brown has requested that the Red Bull senior leadership and garage circles ‘sign an affidavit’ stating that they have never used the bib at the centre of the FIA investigation at the United States Grand Prix.