Red Bull will continue to use Renault engines in 2009, after contemplating switching to Mercedes or Cosworth.
Mercedes' exclusive F1 partner McLaren vetoed the proposed collaboration with Red Bull, and changing to Cosworth was reportedly deemed too great a risk in terms of the power, reliability and fuel efficiency of the returning supplier's V8 unit.
Germany's Auto Motor und Sport reports that the decision was made shortly before the 2009 season finale.
"We have got good foundations," team boss Christian Horner said in Abu Dhabi.
"We have been well supported by Renault as you don't win races and achieve the kind of results we have had without great support from your engine supplier," he added.
